Although I walk along the east attic for hundreds of time but I still can't hear any hollow sound when I;m walking on the floorboard. I noticed some of the board colors are different but when I used each of them with the crowbar nothing happen...Can someone tell me the precise or easier way to find it..?

First, make sure you're in the right section of the attics. From Lucy's bedroom, take a left around the corner and enter the first door you come to. It's in the narrow walkway through the second half of this attic area. Watch for the angle to change so that the camera is looking down on Aline's head. The secret board is actually not in the floor as suggested, but against the wall panel. If you need more specific directions, I can try next post.