Can you please include URLS of your searches and of observations you think shoudl show up in the search but don’t, as well as screenshots of what you’re seeing? It’s very difficult to diagnose a problem without specific details.
I had the same. I wanted to find a slime mould a few days after first finding it and searched for that but it only returned 2 results (I think) so I did the same thing and went to Explore and searched there.