I can't speak for 5ro4, but yes I expect my game to show up if someone searches for "slime". I currently have 7 referrers from searching "Slime Research", and 2 from search by "slime" tag. I also have 5 referrers from google and 1 from another search site, search query obviously unknown.
0 referrals from itch searches for "slime", is bad for me since I think I have less players than I could otherwise, and I think many people searching for "slime" would be interested in my unique gameplay, but they can't find it that way which is bad for them.