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The tool analyses the search terms report for the whole account and finds search terms that may be irrelevant at an account level. These are search terms and phrases that have not converted in any campaign in the account and are not part of the keyword list. The idea is that if the terms are relevant to the business and account they would have either converted or would be part of the keyword list. Based on the methodology we use, you may also discover new keyword themes which you didn't think about earlier.

The suggestions are made using a strategy that is based on data, where it looks at the search terms report and finds all search terms that haven't converted. It then breaks it down into individual words to aggregate the long tail search terms, and after that, we do a relevance analysis against your keywords list. 

If the system finds that there are words from this list that are not part of your keyword list, it will show them as a recommendation because they haven't converted and are not part of your keyword list. 

Due to this approach, you may see recommendations that are relevant to your business, and that can potentially be new topics for you to target. 

You can read more about how it works here.

To add negative keywords at the campaign and ad group level, you can use the Keyword Lasso optimization. In the Turbo Mode in Keyword Lasso, you can see all the search terms that received even a single click and apply filters on top of that. For example, find search terms that have cost more than 'x' and zero conversions or a low CTR.

Negative Keyword Finder analyzes search terms data for the last 90 days.

Currently, the Google Ads API doesn't allow us to write to MCC level shared lists.