Is your girl doing more of a scarf and barf, or is she throwing up more often from an empty stomach? Depending on your feeding routine, you could try to break up the food a little more often throughout the day, especially if you find she is eating too quickly her main meals then barfing shortly after. Also, some cats are sensitive to certain ingredients, I wonder if you might try a novel protein - ZiwiPeak has some good foods you could try, even some air dried raw with different proteins if you are finding she is getting tired of just canned food diet.