I just spent all morning searching through all my Gemini chat sessions for a particular conversation thread we had several weeks ago. I remembered that the later part of the thread had the useful information I wanted, where we went slightly off topic and discovered something really interesting.
The search features are kind of limited as far as I can see. It's basically just simple text string matching, with no obvious way to search using date ranges for example. The results do have a date associated with them, but individual threads don't have a created on timestamp when you are just browsing.
In the end I gave up and got on with the day. Much later I realised that perhaps I had had the conversation in ChatGPT, and sure enough when looked I found it pretty quickly. Seems to me we need better search functionality inside the chats but we also need a way to search across all the different vendor chat sessions all at once.