Emojipedia's Jeremy Burge, following a series of tests with emoji search, a built-in macOS feature that still isn't available on iOS:
Prior to macOS Sierra’s release in September 2016, emoji search for Mac was the opposite: general terms wouldn’t return any results - but if you knew the emoji name you could get it to appear 100% of the time. This is no longer the case.
I do wonder if an internal effort to make these types of search and prediction tools better in the longer term is making them worse for users in the short term.
It's not just that it's bad because the results are somewhat lackluster. It's bad in the sense that typing Apple's exact description for an emoji sometimes doesn't bring up the character it belongs to. If someone is in charge of this feature for the Mac, I hope they can take a serious look at whatever is going on.