Perhaps you should try some spelling variations:
chiet tach » chieu sach
hieu quan » hieu qua, lieu quan, thien quan
cua thong » cua thuong, cua tong, suat thong
cua khong » hua khong, cua phuong, cua thuong
cong hai » cong thai, cong ha, hoang hai
hai ta » hai tan, hai tap, hai ba
ta cau » tao cau, tra cau, va cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu quan) or (chiet tach)) - canh tranh ((cua thong) OR (cua khong)) cong hai ta cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu quan) OR (chiet tach)) - canh tranh ((cua thong) OR (cua khong)) cong hai ta cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu quan) or (chiet tach)) - canh tranh ((cua thong) OR (cua khong)) cong hai ta cau".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu quan) or (chiet tach)) - canh tranh ((cua thong) OR (cua khong)) cong hai ta cau*.