If you get stuck, you can use a Hint to help find an item on the list. The hint button will find the top most clue in the list. A magnifying glass will hover over the clue in the image for 3 seconds. Tap the missing clue to remove it from the list.
You start with 3 hints and can earn a free hint in every puzzle. Each of the puzzle packs have a hidden hint. The hidden hint is located on the bottom left of the puzzle pack or on the start screen for each puzzle. The start screen tells you whether the hidden hint has been found for each puzzle. You can also determine if the hidden hint has been found for a puzzle by looking for the mini magnifying glass on the puzzle thumbnail.