Level 169 is quite hard. You should focus your efforts in two areas: destroying the crates in the center of the field to clear some space and release the pre-set Dynamite power-ups) and creating bombs to get rid of the granite. If you disregard the granite, you may end up getting completely stuck as only bombs can destroy it. As for the chains, it’s rather easy to remove them with Lightning power-ups. Combo explosions are extremely effective on this level – try to explode as many bombs in a single move as possible.
You should also check out this video that shows how we got through level 169.