Teaches don't like questions.

Do you have ever noticed that some teachers don't like deep drive into questions asked by the students and try to think about it. I have experienced that whenever I ask a question about subjects like math or science which are related to book not outside of it but not explained in book. My teachers just want to tell anything which does not make any sense and is quite unrelated to the question I asked they even try to distract me from my real questions. I am not saying everyone is like that maybe I have a bad luck.