In Finder, there is the search box in upper right. Type something like "Blue shirt", and one of the options that pops below the box will be:
"Content: Contains 'Blue shirt'"
It should do a visual search for some common things, as well as OCR in image text.
Thank you for your reply. My initial testing yielded no results, but simplifying the search term to single words (like "mountain") worked to turn up a few (among many that should have appeared). Seems like there may be room for Desktop Docs, at least until Apple's own ML search improves.
It should do a visual search for some common things, as well as OCR in image text.