Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
thiet qua » thien quan, hieu qua, thien quy
doanh cua » doanh luan
dien than » dien thanh, dien toan, dien phan
vien than » vien thanh, vien nhan, viet thanh
danh cua » manh cua, dinh cua, dan cua
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 cua) or (doanh cua)) nguoi viet ha hoc ((dien than) or (vien than))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: giao trinh thiet qua ((danh cua) OR (doanh cua)) nguoi viet ha hoc ((dien than) OR (vien than)).
• Adding a wildcard symbol may retrieve word variants: giao trinh thiet qua ((danh cua) or (doanh cua)) nguoi viet ha hoc ((dien than) or (vien than))*.