It may be possible to lift the keys out and clean around then with distilled water and maybe use some sort of silicon dusting product to use for lube.
It may be possible to remove the keyboard and douse it with distilled warm water and blow dry it off and dry it with a hair dryer.
Worse comes to worse you may have to purchase a replacement keyboard.
Most laptops are sort of difficult to decide how to take apart. Usually snaps hold the last parts on and cover up some small screws. It is all very small parts and a bit delicate.
Why did it take me over a year to phone in a problem to ATT?