What does "questions that make you think" mean? Does it mean "tricky questions" that you don't know or "questions" that enlighten you?
When I use that phrase, I mean it was a question that actually made me think, and it/was enlightening.
It means the question really makes you think and use your brain. It's not just a quick, simple, easy answer.
To me its a question that makes you think wow I never knew that, and then sometimes its a question that make me think, wow what an idiot.