You have to work on shooting some vertical striped candies down through the jelly and then start using the jellyfish to clear up the remaining candies. All of the spots are double jelly, so each needs 2 shots. You will never get any pieces in the jelly area, and another way to attack it is drop a horizontal striped candy down the middle and then shoot a vertical one down to set it off.
Patricia Frederick’s Tips for Candy Crush Level 246
Try to clear some of the jellies before you release the jellyfish using vertically striped candies or striped/wrapped combos. This will force the fish to eat the jellies that are harder to reach.