Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
vien thanh » viet thanh, tien thanh, dien thanh
qua danh » luan danh, luat danh, quoc danh
dien han » dien phan, dien than, dien dan
qua dan » qua ban, cua dan, mua dan
viet ha » viet nam
ha hoc » hoa hoc, nha hoc, va hoc

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: giao trinh thiet ((qua danh) or (qua dan)) cua nguoi viet ha hoc ((dien han) or (vien thanh))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: giao trinh thiet ((qua danh) OR (qua dan)) cua nguoi viet ha hoc ((dien han) OR (vien thanh)).
• Adding a wildcard symbol may retrieve word variants: giao trinh thiet ((qua danh) or (qua dan)) cua nguoi viet ha hoc ((dien han) or (vien thanh))*.