After revealing the cylinder you would need to choose the correct symbols.
What is the hint?
Can you elaborate more?
What are the relations?
I didn't find any hints in the game about this. But I can give you a hint.
Pick the odd one out.
Pick the symbols that don't match others. Like, in the first one, pick the symbol that does not relate to Christmas.
The present with two lines going same direction
Take the candy cane to reveal the safe.