How to get a book indexed by Google Scholar: How to upload to Google book search and what makes a book scholarly?
As at the time of writing, the other answers here are incorrect: you certainly can manually add entries, including books, to your Google Scholar profile. That is done directly on your Google Scholar profile page: there is no need to use some other indexing system.
When you are logged in to the Google account that corresponds to your profile, you'll see this &quot;+&quot; icon on your profile, which allows you to add records:

Select &quot;Add article manually&quot;, and when you get to this dialog box, select &quot;Book&quot;, and enter the appropriate details:

Perhaps just as importantly, you can also select records to delete (when Google Scholar's algorithm incorrectly adds someone else's publications to your profile), or you can select records to merge (when Google Scholar picks up slightly different citation details and thinks that a single publication is actually two, very similar, publications).