Hey Evan, that's a cool idea. There's nowhere within Clay to see a log of your previous searches across tables, globally.
But within an individual table, though, you can view the source(s) used to supply the data. See the "Modify existing source configurations" section here:
https://www.clay.com/university/guide/sources-overview
You could use that to modify an existing Find Companies search, for example, or refresh your memory on how you got a set of results.
If we did have something like a history/log of previous searches, I'm curious to know more about the use case/workflows it would unlock for you.