How does the search function work and why does it sometimes not work from different instances when searching All?

In other words -

  • I search for a community that exists on Lemmy instance A (e.g. midwest.social) from Lemmy instance B (e.g. lemmy.ml) and it finds it.
  • I search for that same community from Lemmy instance C (e.g. lemmy.one), and it doesn’t find it.
  • Lemmy instance A, B, and C are all connected / federated.
  • To add to the other answers, when you search for the community that isn’t registered yet, it will take 10 seconds or so for it to appear in the search, slower than everything else. You also have to type out the full name to register it.