Can gastroscopy and negative blod test miss out on gluten intoleranse. With persistent problem and nutrient deficiency is there indication for new test?

Yes and no. The "gold standard" for diagnosing celiac disease (gluten allergy) is a biopsy of the small intestine. There are a few blood tests that are typically ordered and are usually positive in people with celiac disease, but they are not 100%. The stomach is usually not affected by gluten allergy. Rather than undergo more testing, go gluten free for 4-6 weeks and see if your symptoms improve.
Not usually. Assuming the correct tests were performed, negative results should rule out the disease. If you are still having symptoms though, you should try eliminating all gluten from your diet for 2 weeks and see if you feel better.