Don’t ask me! Your answers may come from above! (6,5)
I believe the answer is:
heaven knows
If this is the answer, I'm afraid I cannot explain it.
Can you help me to learn more?
(Other definitions for heaven knows that I've seen before include "It's anyone's guess" , "Search me!" , "I swear it" , "Information is available above" , "I've no idea" .)