Ask HN: I feel like I'm in a filter bubble. How can I “expand my horizons”?

Hi! I've noticed that I've stopped rapidly expanding my knowledge about the world. I hang out on the same websites(HN, reddit), learn the same topics(programming plus couple of hobbies), hear the same ideas.

Nothing has dramatically "expanded my mind" or changed my opinion in the past couple of years. I try to read a lot but it seems like all the books I read are on the same topics, and just repeat the same ideas.

How do I fight that?

I think there's a lot of great areas of knowledge and new ideas in the world that I have no idea about, but I don't know how to find them.

I feel like I've explored pretty much everything that I care to know about the world, and all that is left is to go deeper into the areas I'm already aware of(science, tech, etc), but of course it's probably not true.

What do you do about that? And what are some things that you've discovered in the past 5 years that you weren't aware of before?