Talk to General Physician on Regular Loss Of Blood Hb

My father was feeling extreme tiredness and dizziness since around a month. He was admitted in nearby hospital where his blood reports states that he is losing haemoglobin on daily basis. On doctor's prescription he is already getting Vitamin B12 intake. I am still not satisfied with the treatment as the doctors are still not able to diagnose the cause of blood loss in his body after numerous of different tests including ultrasound, CT scan and now CT Angiogram. Till now he has been transfused around 10 bottles of blood and it seems to me only temporary measure to maintain blood Hb. I am attaching the most recent test report. Plus I believe my dad needs supplement for blood iron and Hb. I found one online but the medicine is from UK. Can some doctor suggest me similar medicine in Pakistan and also give valuable suggestions on this test result. Many thanks in advance