Took me about 10x to get though. One thing to do is to use the chocolate balls you do make to eliminate a colour on the board, as opposed to pairing it with a stripe.
I like to have a couple unbroken chocolate ball on the board and eliminate one colour, check for fives, and then break another colour.
This often sets up fives for you and you may get a couple more from that if you look really carefully, and then repeat this again. This is how I passed this level.