Perhaps you should try some spelling variations:
thanh trung » thanh tung
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
cong thanh » dong thanh, cong trinh, truong thanh
trung cua » truong cua, trung tuan, trung cap
cong tan » cong tac, cong san, cong ty
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: theo chieu sach - thanh trung cua cong ((cong thanh) OR (cong tan)) ((phan lap) or (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - thanh trung cua cong ((cong thanh) OR (cong tan)) ((phan lap) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sach - thanh trung cua cong ((cong thanh) OR (cong tan)) ((phan lap) or (phan dau))".
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - thanh trung cua cong ((cong thanh) OR (cong tan)) ((phan lap) or (phan dau))*.