This has been in place for a while, but I just added Discourse to it: https://docs.edx.org/search
This aggregates documents across GitHub, Confluence, ReadTheDocs, and so on, to give you a unified search of “all” Open edX information.
Give it a try and let us know how to improve it. It’s built on a Google Custom Search Engine, so we don’t have a ton of control, but we can change what URLs it includes and excludes.