at least i could find it, you may be confused about the 0 subscriber, that only means 0 persons of YOUR instance have subscriped to it maybe a link like !nba@lemmy.world works better but i am not sute because the underlaying url looks like the same bit the exclamation mark could trigger something helpful

with this url: https://ani.social/c/nba@lemmy.world what looks like the same, so it could be possible that your instance actually did not know them before and only federated them actually a few moments ago.
At least newer servers need time and that sounds like the problem that was way more present a month ago where a lot of new communities and servers popped up

I think the fix was to look for the instance and wait a bit but i am not sure

for finding communities i suggest taking a look at lemmyverse.net instead of the native system

Hello! It may take a while for newly-found communities and posts to process. If you subscribe to the community, the posts should start to appear. I can access !nba@lemmy.world but the posts haven't shown up yet. It will take a while but it will sync in time.

To search for communities nobody has added yet, you need to add the exclamation mark in front, as the others have indicated. Do that with your search, and it should link after a few seconds. If it doesn't, try click search again, things sometimes are a bit slow since it's federation based.