Objects are not hidden but spawned after time
You go through the same spot 10 times and don't find anything. The on 11th time you suddenly find it exactly where you checked 10 times before. The game does not hide object. It spawns them later, making you spend more time in the game to watch ads. Don't get me wrong, I don't mind ads (we all have to make a living), but the game is just cow milking. Only the cows are the real people.