Focusing issue with my 50mm F/1.8

I always face problem of getting sharp photo with my 50mm lens. I can only think of 2 reason on why my photos not sharp. One is my handshake.... and another is my lens problem that needs calibration.

So I did a test a moment ago on CT suggestion. I mount my camera on tripod and take some shots. Below is one of the shot that I took just now. I point the AF to the remote, and wua la.... see the remote, sharp sharp leh. Thus I can conclude that it is not the lens problem that photos I took is not sharp, it is due to my handshake. LOLx..... ^ ^