My cbc exame show mcv low 77.3 and mch low 22.5 what is the causes and is that mean iam treat thalassemia . hg electrophoresis all normal afsa2?

That is just: Slightly low. In a young woman the most likely diagnosis is iron deficiency.

Iron Deficiency: Your numbers are only slightly low. You are in a region where beta-thalassemia is common, but you hemoglobin electrophoresis does not show that. I trial of iron supplements and a repeat of your numbers in a few weeks makes sense. If not better, then additional tests may be needed.

Low MCV often IDA: I agree with other responders that a low MCV is likely iron deficiency anemia (ida). However, instead of assume that and treat, some simple tests can be done. CBC w/diff, peripheral blood smear, reticuloctye count, EPO level, ferritin & other iron studies. Ferritin tends to be the best iron study for determination of ida. Also a ua (for microhematuria) and fob (fecal occult blood test).