I see in the source code on certain threads (SHT31 humidity, various Atlas threads, etc) that the meta robots tag is set to "noindex" rendering it invisible to search engines.
I also see that this isn't universal and there are certainly other threads that are being indexed. So are administrators setting certain threads to "noindex"? If so, any reason for that?
I also checked the robots.txt file to see if there were specific instructions for an alternate path for robots to index and couldn't find any.
That would explain why I never get any results pages when I search on terms I know are present in some threads here.