I understand where you are comming from 100% i too have a chihuahua who is on the smaller end of the scale. And he too will find something to eat off the floor no matter how clean it is. And my little chi has the same problem somtimes what I do is give him a little of the science diet canned puppy food. It doesnt have any biprodcuts in it and its not too mosit but not too dry. Also sometimes they just need a little more water. As far as what your feeding him goes it could be the ingredents in the food, if they are bi products that can cause diffculty for a smaller chi or any chi to go potty. I feed mine an all natural diet. And honestly it doesnt cost anymore then the ones you buy an the petstores. I am going to include the link just in case you or anyone else is intrested. I would ask your vet if diet could have anything do it with it and if he.she have seen any other chi's or small dogs come in with the same or similar problems. I hope this helped somewhat and if you have any other questions feel free...chihuahuas can be tricky little things...
Chi Hugs-----

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