iOS Mail search function does not work properly

This is a follow on from a previous thread on the same subject from a couple of years ago, referring to iOS 15. As far as I can see, the iOS mail search facility STILL doesn’t work, and here I am with 17.3.1. The problem is easily demonstrated: I can see a number of emails on my screen from the same sender and with the same subject. However a search on that sender, or that subject, does not return all of them - sometimes none at all.

It is clearly a bug, not solved by the various workarounds/tutorials suggested in this forum. Come on Apple, please just fix the darn thing, and soon. Thanks.