Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
dung cong » dung trong
tranh va » tranh van, trang va, trinh va
cong tan » cong tac, cong san, cong thanh
chan cau » phan cau, chinh cau, nhanh cau
va dung » van dung, va duong, vat dung
can cau » van cau, ban cau, ca cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu manh) or (chieu tinh)) - canh tranh va dung cong tan ((chan cau) or (can cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (chieu tinh)) - canh tranh va dung cong tan ((chan cau) OR (can cau)).
• Adding a wildcard symbol may retrieve word variants: doc ((hieu manh) or (chieu tinh)) - canh tranh va dung cong tan ((chan cau) or (can cau))*.