I bought a I go to open it and it shows me that it opens, but when I go to my inventory it is still the chest, not the items from inside the chest.

nvm

You have to choose a single item from the chest.

well that explains it. lol such a facepalm moment

[edit]

I guess that is what this writing on the top means.... Lucky you! You get to choose a specific item from these choices:

Yeah, it's a pity it doesn't act as a trunk. Choices like that are tough! xD