I'm sorry to hear your daughter is suffering so much. She needs to see a pediatric gastroenterologist. Her regular pediatrician should be able to recommend one. If she has a history of anemia and intestinal ulcerations and mouth ulcers and weight loss, there's a bunch of red flags.
Not sure if you're super-familiar with the way the digestive system works but it's helpful to understand it as much as you can. It can be kind of confusing.
The pathway goes like this: mouth, esophagus, stomach, small intestine (consists of the duodenum, jejunum, and ileum), large intestine (also called the colon - consists of the cecum, ascending, transverse, descending, and sigmoid colon), rectum.
The small intestine is super long and loops and bends around all over the place. This is where most of your digestion and absorption of nutrients takes place. When you get a "small bowel study" (also called a "small-bowel follow through" or "barium swallow"), they are taking several x-rays of the small intestine after the patient drinks a barium milkshake, which helps the x-ray pick up on all the loops and bends in the small intestine; they can look for narrowing in the intestine this way, which might indicate inflammation in there.
Another way to image the small intestine is with an EGD or upper scope; the only disadvantage here is that the scope can only go as far as the duodenum, so it's not a very reliable study unless you're particularly interested in the esophagus, stomach, or upper duodenum.
A colonoscope is a flexible tube inserted up the rectum into the colon; like the EGD, there's a camera attached to the end, which allows the doc to see the interior of the colon and check for ulcerations or any other signs of inflammation.
I hope this helps you navigate the terminology a little better...
Anyway, like I said, it's definitely time for her to see a pediatric GI. There are SO many things that can go wrong in there and it might take more testing to figure it out. Nothing is ever absolute in the GI system (life would be much easier if docs could tell us definite answers, wouldn't it). Best of luck and keep us updated.