I have a Lenovo laptop and the screen flickers on and off,is there something I can do myself?

I have dropped the computer a couple of times in the past and since then (I think) the screen flickers on and off, and its an anoying issue cuzz I need to move the screen every time it does it, and I took the computer with a person that suposed to fix it but he doesn't seems to know what he's doing. Is there some thing I can do on my own? if some one can help...