Maybe if you enabled "show nsfw content" in your settings. Screenshot for search results of "asian": https://i.redd.it/9jbms02e3mn61.png
The search filter is either a binary, or there's just so much porn for everything that it doesn't matter.
Other ethnicities, also show up with some porn results, but not nearly as extreme as for "asian". e.g. for "white" and "black" it was about a third of the top 20.
If you just recently enabled the setting in your user profile, probably there is just some caching on reddit's side so it is still serving the old results from before you enabled that.