Here's how shop works. If you see portrait with special images on it. You can hover over them to get hint. If you click them you will buy them for some coins and they will be unlocked in animation gallery.
The one's that are like in the image above require you to buy hint. After hint is bought their image sprite is revealed and you can see hint by clicking on them. But they don't get unlocked in animation gallery. You have read the hint and unlock them yourself.