Perhaps you should try some spelling variations:
canh thanh » canh tranh, danh thanh, anh thanh
chong cong » cong cong, thong cong, cuong cong
san chong » san chang, san cong, san khong
cong hoan » cong hoa, dong hoa, cong san
hien anh » hien hanh, thien anh, tien anh
dien anh » tieng anh, dien dan
can cau » van cau, ban cau, ca cau
van hau » van ha, van hai, van 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 ((hien anh) OR (dien anh)) - canh thanh san chong cong hoan ((can cau) or (van hau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien anh) OR (dien anh)) - canh thanh san chong cong hoan ((can cau) OR (van hau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien anh) OR (dien anh)) - canh thanh san chong cong hoan ((can cau) or (van hau))".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien anh) OR (dien anh)) - canh thanh san chong cong hoan ((can cau) or (van hau))*.