Perhaps you should try some spelling variations:
tieng cong » tien cong, tieng chuong, tieng muong
hieu lang » chieu sang, hieu quang, nhieu tang
tranh hoc » thanh hoc, tranh cuoc, tranh duoc
hoc tieng » hoc hien
dan than » dan chan, ban than, dan toan
van than » van thanh, van thang, van tuan
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 hoc tieng cong ((dan than) or (van than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - canh tranh hoc tieng cong ((dan than) OR (van than)) cau.
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - canh tranh hoc tieng cong ((dan than) or (van than)) cau*.