How to find more classic/world cinema films?

I have always been somewhat into movies but recently have dipped my toe into non mainstream films. I am subscribed to the Criterion Channel as well as Kanopy and I am trying to work my way through the Criterion collection, which is currently a big part in how I decide what to watch. To be honest I would have missed a lot of solid films either due to sheer ignorance or not giving them a chance, had they not been a listed film.

My question is how to find those gem films that aren’t a part of the collection. Additionally, I would love to hear your “must watch” films that I might have overlooked that I can add to my watchlist that aren’t a Criterion numbered film.