Fire the Blue bird head-on into the ice blocks in the middle of the level. Ideally, you want to leave a clear path for the next bomb. Instead, use the first White bird to clear as much debris as possible from the middle. With the next White bird, bomb the jewel in the bottom-left and ricochet into the wooden foot for that tower. What remains is a lobbing Yellow bird through the middle of the structure, just left of the horizontal stone block.