Although rose hips are one of the safer treats, you do want to limit it to one treat a day max. If you mean you are giving 5-6 little pieces of crushed rose hip that's probably fine it's a limit of one whole rose hip a day. If you are going to give another treat then only give that treat as the treat for the day and no rose hips. You don't want the chin filling up on treats and not eating it's actual food.
I don't feed goji berries, but I'm pretty sure those should be limited to about one a month. I figure why give junk food at all when there are safer options, some chins have no issue with them, others have ended up with diarrhea or bloat after eating just one goji berry. Keep in mind that chins can't process sugar very well and their food already has sugar in it, so any treats you are giving is additional sugar on top of what they are already getting everyday.