Perhaps you should try some spelling variations:
thiet thanh » thien thanh, thi thanh, viet thanh
thanh tung » thanh cong
cua thuong » cua truong, cua phuong, ca thuong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tung cua » trung cua, tuong cua, dung cua
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
phan cau » phan cac, phan tu, phan lap
phan dau » phan tu, hang dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet thanh - thanh tung cua thuong ((cong tan) or (cong san)) ((phan cau) OR (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet thanh - thanh tung cua thuong ((cong tan) OR (cong san)) ((phan cau) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet thanh - thanh tung cua thuong ((cong tan) or (cong san)) ((phan cau) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet thanh - thanh tung cua thuong ((cong tan) or (cong san)) ((phan cau) OR (phan dau))*.