When I used Google to locate documents on my client's website with the word (e.g.) "Vendor":
Unless I'm missing something, the returned results included a doc where "Vendor" is included in the screenshot of a menu (an image), but not the actual text...unless I'm missing something, not in the actual text. Unless you include the page tree on the sidebar. (This doc is in Confluence).
Is Google search now smart enough to extract (simple) text from images?