Can I Sue this restaurant or put them out of business?

My grandmother and I went out to lunch at an asian buffet called Sakura Buffet in Lancaster, CA. My grandmother and I noticed that there was flies going into the food. But sadly it was after we at a little bit of food. We both think that we ate some flies that we didn't see. My grandma told one of the workers and all they did was fan the flies away!!! I felt so disgusted. After a while we started throwing up and had to go to the bathroom.We think it's food poisoning. It' not like were greedy or anything but this place needs to be shutdown!