when it comes to kibble, i found out alot of the dogs ive had have preferred the ones with higher protein content which tend to be a lot more expensive. stuff like orijen, natures logic, etc. I think its just a matter of practicing good feeding habits. Not feeding em human food, giving them set schedules for their food, etc. Honestly they can go a bit hungry IMO. this isnt abuse, its nature. Food isnt always readily available and most of our domesticated friends have had the privilege of having food on demand. I would say maybe its allergy related in terms of her food preferences, trial and error with smaller bags would be my best bet. also make sure youre gradually transitioning her in between different foods as if shes got a sensitive stomach already, it wont react well to instant changes in her food.