Sometimes, you have to free Match 3 In A Row from chains or destroy walls to complete the level.
On every level, you can get up to 3 stars. Next world unlocks when you reach 160 stars in the previous world.
To make the game saga more fun, make matches of 3 to launch meteors, which will help you complete the level. Meteors will either crush the squares under Match 3 In A Row, or the jewels under the candy to let the candy fall down.