THanks. I 've seen that document page. It isn't very thorough. I don't know enough to program, but did copy the existing example of a Dynamic File Search, which included a JSON element, so I just replicated that in order to drill one level deeper into the file structure (trying as I mentioned to find folders inside of folders). I haven't tried deleted the second JSON utility (see chart above) because it seems to be working, more or less.
The trouble is that I have a zillion folders; keeping track of their names is nigh impossible. But I do know that they have a relative location, and was hoping to simplify life by finding a way to drill down.