Perhaps you should try some spelling variations:
tranh hoc » thanh hoc, tranh cuoc, tranh duoc
tang cong » tang cuong, trang cong, dang cong
hoi hieu » hoi phieu, hoi tieu, moi hieu
hoc tang » hoc bang, hoc tan, hoc tieng
dan than » dan chan, ban than, dan toan
van than » van thanh, van thang, van tuan
ho hieu » ho chieu, nho hieu, co 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) OR (hoi hieu)) lang - canh tranh hoc tang cong ((dan than) or (van than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho hieu) OR (hoi hieu)) lang - canh tranh hoc tang cong ((dan than) OR (van than)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho hieu) OR (hoi hieu)) lang - canh tranh hoc tang cong ((dan than) or (van than)) cau".
• Adding a wildcard symbol may retrieve word variants: ((ho hieu) OR (hoi hieu)) lang - canh tranh hoc tang cong ((dan than) or (van than)) cau*.