Ask HN: How do you become a better problem solver?

I understand that solving new problems is helpful but how do you ensure that you don't develop specific domain knowledge and instead improve your overall problem solving capabilities.

I came across an article published by a MIT professor on solving complex problems. I'm going crazy right now because I can't seem to find it anywhere. However, I did come across this site which looked interesting. Perhaps you'll get something out of it.

https://ccmit.mit.edu/problem-solving/