It doesn't make sense to me but the geniuses at Zynga decided that after a couple of plays to change the requirements from 10 items to find to 5 items... or maybe I just got a lazy Customer Service agent who didn't want to report a new error I've found... any how I was told this scene was designed to only find 5 items... so as I mentioned before try to get a high score early.'
EDIT: Zynga has fixed this scene so it is working like all the other scenes do (having 10 items to find)
Unfortunately there doesn't seem to be a way to go back in to replay this scene.
Maybe it will make a reappearance in the future when we get closer to solving the mystery of Ramsey Manor...