The most common cause of water entry is blockage of the four sunroof drain tubes with dirt and leaf debry. These tubes channel water which gets past the sunroof seals through the pillar areas of the car down to exit tubes near the tires. If you can locate them, you can take a stab at clearing them from the bottom. I've used weed wacker plastic line to do so. There is more information on this forum discussing this topic in detail.