You will be able to do as many combos as you want in the game, but one of the most important things which you should always keep track of is your moves and the level's goals.

You should always try to complete the game's goal within the number of moves that you have, because this will mean that you are going to pass the level and receive a star which you can use to decorate or progress further into the story.

The number of moves that you have will be shown in the top left corner of the screen while you are playing a level, and right underneath it you will have the level's objective. I suggest that you always try to reach this objective within as few moves as possible, because the extra moves you have left will count towards some extra coins in the end.