Case Study: Books Express AdWords Campaigns

books-express-logo (1)Context:

Books Express is exclusively an online library with over 7 million books, most of them being specialty items in English, German, French, Italian or Spanish. The specialty books covered hundreds of domains, from cultural anthropology or criminology, to biochemical engineering or edilitary engineering. Books Express also sells fiction, children, or teenager books.


A great variety of books from diverse industries comes with a series of great challenges for configuring PPC campaigns:

#1. Targeting a niche public, who is actively looking for or is interested in specialty books (ex. corporate, professor material, etc.)

#2. Including as many available products on the website as possible, in order to reach those users whom are looking for specialty books (ex: they are looking for an author or a title of the volume)

#3. Excluding irrelevant searches, which on this niche have a very large volume (many people look for PDF books online, torrents, ebook reader format books, audio books, etc.)

#4. Increasing the volume in sales, as well as of the value of the shopping cart


1. Google Ads Campaigns: Dynamic Search Ads – the best instrument to answer challenges #1 and #2. Dynamic Search Ads dynamically match the search between the search of a user and the pages of the website without it being necessary to set these keywords in dedicated ad groups. Thus they could cover the extremely specialized volumes of incoming searches that cannot be manually added in campaigns as you can see in the example presented below: “atlas anatomie netter”

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2. Google Ads Dynamic Remarketing Campaigns

If by a classic Remarketing campaign you can only display banners of text ads to those whom have visited your website, but have not purchased anything, Dynamic Remarketing helps you include in those banners or text ads specific images or messages, depending on the products the user has seen on your website, without purchasing them. Thus, the message becomes much more targeted, more relevant, and this helps increase the chances of the followed user to return to the website and purchase.

The creatives from a Dynamic Remarketing campaign are configred based on pre-set models available in Google Ads and they look as following:


3. Tracking the value of the transactions directly in Google Ads

For any online library, one of the most important performance indicators is the value of the transaction (Total Conversion Value). In Google Ads this indicator shows, along with the total number of campaign generated online orders (Conversions), the value of these orders that are dynamically recorded from the shopping cart. Applying this setting you can see (from the example below) which keywords have generated the most valuable transactions.


By tracking the value of the transactions you can make efficient decisions regarding optimizations on a campaign or even keyword or ad level. Thus, even if it is necessary to pay more per click for a keyword and you have a higher cost per acquisition, the value of the transactions coming from this word could justify keeping it and activating more aggressive bidding strategies. If this keyword brings you more clients that buy more products or more expensive products, there is no reason to eliminate it from the campaign, but more likely the opposite. You could optimize in order to attract more traffic from the source and also increasing the profitability of the campaigns.

4. Structuring and segmenting the Google Ads Search campaigns

When choosing the keywords from a capmaign or when making a decision to structure your Google Ads account as campaigns and ad groups, you have to keep in mind an important crteria: who is the consumer I wish to target? Knowing the answer to this question you can organise the Google Ads account depending on the search behaviour of the targeted audience and their interests. Here are two examples from the used campaign segments:

» Best Sellers: People interested in the newest appearances, in the “trending” books. Example of a campaign: Colouring Books for adults (Secret Garden), Outlander, Game of Thrones.


» Publishers and Industries: People interested in certain publisher books (ex. Farma Media) or from a certain industry (ex. Medicine or even more specific: Dermatology).


Google Ads Search campaigns have been thematically segmented depending on the Industry, Sub-Industry, bestsellers, publishers or authors, in order to maximise the click-through rate and quality score. A Quality Score higher than 8 determines how low the cost per click will be in order to display the ads.

For maximising the relevance of the ads displayed on Google Search for the public segment chosen by targeting on a keyword level, all ads were adapted, not only to contain the exact expressions users are searching for, but also to display ad extensions that are relevant for the specific search. For example, for “Medicine Books” ads has for extensions specific Sitelinks for the Medicine industry such as: Surgery, Nursing, Medical Specialties, Internal Medicine.

However, for “Engineering Books” we can find different extensions: Electrical engineering, Industrial Chemistry, Quality Control, Biochemical Engineering. With a simple click on these extensions the user will be redirected to the relevant category pages in the online library.


6. Exclusions

On Google Search we have added, based on the made optimisations, over 3200 negative keywords on a campaign level and over 2500 negative keywords on an ad group level.Negative keywords help us exclude the irrelevant searches for the sold products and to reduce costs. Among the chosen keywords we had: “download”, “free”, “audio”, “torrent”, etc.

From the Display Remarketing campaigns, sites have been periodically excluded. These sites were not relevant for our targeted audience, so we reached an aproximate of 1100 negative placements and topics. With these optimisations we have made sure that the banners are displayed in relevant contexts, favourable for generating acquisitions, thus saving hundreds of RON per month.




Graphic 1: Shows the daily 8 month spread for the Google Ads account.

Orange line = conversions (customers)

Blue line = costs / acquisition


The cost per acquisition fluctuates depending on many factors, but through constant optimisation, it maintains on a monthly or quarterly basis between certain limits, to maintain profitability of the campaigns. With a lack of periodical optimisation in a Google Ads account, the cost per acqusition would increase.


Graphic 2: Shows the spread on the same 8 month period, but you can see this on a monthly basis. Thus you can notice the trend of an increase in sales, based on optimisations and a constant cost per acquisition, so a profitability of the campaign.


» Cost per acquisition<10€ in Google Ads on the non-branded components

» Average conversion rate of 1%, in some months even exceeding that value

» Conversion rate > 1.5% on the dynamic compoents: Dynamic Search Ads, Dynamic Remarketing

Graphic 3: The Dynamic Remarketing component had a cost per acquisition 2.3x lower than the classic Remarketing and a 3x higher conversion rate.


About Alexandra Zaharia

Alexandra Zaharia is Head of PPC @Today's.