Is it some search algorithm that is so new, unusual and groundbreaking you can't talk about until it patented, or what?

I really hope you are right and have your priorities straight when it comes to search. I'd love for a way to search for usages of a class::method, or for strings that contain the text "hello" or for variables named foo. And if you integrate that into the code itself, Ctrl+click a class method to find all usages, maybe even usages in other repositories, so I can see how other people use a certain library.

And of course good old regex search.

Sourcegraph does this quite well if you need.

They are tagging so much code with text, that i'm sure they have something groundbreaking.