Comment by yorwba

You can use undermind.ai on the free plan. I made two searches when they launched and still occasionally get updates with new relevant papers. Unfortunately, those papers are typically only new and relevant, but not novel. (Not a knock against the search quality. In an area where data acquisition is expensive, everyone working with the same handful of small datasets is probably unavoidable.) But the initial searches surfaces some old papers I had missed, so I'd say it's worth a try.