Thank you both! Something I should have learned years ago, but had been “spoiled” by ‘Marvin’, which loads title/author info to local app (from Calibre database stored on Dropbox)….and search is just of those items. I am now trying out ‘Mapleread’ which interfaces via OPDS.
I was easily able to use the (now obvious) search parameters in browser to the content server. Just for the heck of it, I tried in Mapleread using OPDS. The same searches seem to also work there. (It just doesn’t warn you about Apple’s smart quotes 😀

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