On some levels of Candy Crush Saga you need to get ingredients down the playing area and out of an exit, usually at the bottom.
Here in the picture you can see cherries at the top,l which have to be moved down to the bottom and out of the exits.
This example is fairly simple.
The main thing to remember on these levels is to concentrate on getting the ingredients to the exit holes, sometimes at the expense of making special candies.
As you progress in the game the boards get more complicated and sometimes several seemingly unrelated moves have to be made to get the ingredients down and off the board.
Here is level 81 Candy Crush Saga.
If you look in the pink area on the left you will see there are 3 cherries to be brought down.
Sometimes you will see nuts also, it depends on the level.
But first you have to remove the licorice whorls and unlock the locked candies to get the cherries to the exits at the bottom.
Make specials if you can to begin with, which will help to remove the obstacles, then concentrate on getting the ingredients down.
Once you get the first one off the board the next one, with luck, will drop down after your next move, so try to make your next move in an easy place, ie. the middle of the board, or away from any other obstacles.