Rope-through-wooden-block puzzles consist of two blocks that are apparently tied to each other. You have to remove the smaller block from the larger one without untying or breaking the rope. These puzzles are commonly known as disentanglement puzzles because the solution lies in untangling the rope holding the blocks together.
Pull the rope through the holes. The small block will slide towards the larger block and a loop of rope will hang down from the bottom of the puzzle.
Turn the puzzle inside out by putting the loop through the hole at the top of the puzzle and threading it up through the hole on the bottom of the puzzle.
Put the small block through the loop and remove it from the puzzle.