Re: Advanced Search plugin needed
You could also potentially use the “Search Engine” plugin by Scott Kingsley Clark:
https://wordpress.org/extend/plugins/search-engine/
It works as a spider so it indexes all content on your site (so I’m guessing it would include BP content)… I should state that I haven’t used this though.
OK, I tried Scott’s “Search Engine” plugin on BP. It is well intended, but still in very deep beta. As far as I could tell, it was only indexing blog posts, and I couldn’t seem to test even that, because each time I hit the search box, the result was always a single, non-clickable Google Search Result unrelated to the content that should have been indexed.
Google Custom Search also seems to have issues with BP, as it was not indexing forum posts. Perhaps a site map needs to be submitted for GCS to pick up on forum posts?