Perhaps you should try some spelling variations:
cong khanh » cong thanh, cong khan, cong nhan
hieu lang » chieu sang, hieu quang, nhieu tang
tranh cua » doanh cua, manh cua
cong hach » cong sach, cong thanh, trong hach
cua dung » cua dang, cua dong, qua dung
toan ban » van ban
ho hieu » ho chieu, hoi hieu, nho hieu

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 lang - canh tranh cua dung ((cong hach) or (cong khanh)) toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - canh tranh cua dung ((cong hach) OR (cong khanh)) toan ban.
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - canh tranh cua dung ((cong hach) or (cong khanh)) toan ban*.