Hi, thank you so much for playing and the feeback.
Oh, it's true, sorry. I added a little description in the project page explaning this while i cannot update the game.
To use the items you need to go to them, so the item will be equiped and you can use it as a gun firing with mouse. You need to put they back in the right place in order to use other item or interact with mud puddle. I'm thinking of simplifying this mechanic.