Come to think of it, it could've also been that that community maybe actually did show up in the sh.itjust.works search results when you searched for just "piracy", but that the community was lower down on the page and sort of blended in with the other results, so you didn't notice it.
You can try searching just "piracy", and then choosing "communities" from the drop-down menu just to the left of the "subscribed" button. That should make the search results show only communities, so that it's harder for communities to get buried by or hidden among irrelevant results.