If you block a user, that user will not be able to see your questions and answers. You will not be able to see blocked user's questions and answers as well.
＜How to block＞
- Tap or Click the options icon (...) on the profile, question, answer to bring up the options menu.
- Tap or Click [Block].
＜How to Unblock＞
- Tap or Click [Settings]
- Tap or Click [My account]
- Tap or Click [Blocked users]
- Tap or Click [Unblock]