Perhaps you should try some spelling variations:
sinh sach » chinh sach, sinh san, sang sach
cong lang » cong vang, cong luong, cong quang
tranh he » trinh he, tranh ha, tinh he
he nhung » hee nhung, ve nhung, me nhung
cong san » cong tac
hang tai » hang va, dung tai
han tai » nhan tai, van tai, toan tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sinh sach - canh tranh he nhung ((cong san) or (cong lang)) ((han tai) or (hang tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sinh sach - canh tranh he nhung ((cong san) OR (cong lang)) ((han tai) OR (hang tai)).
• Adding a wildcard symbol may retrieve word variants: hoc sinh sach - canh tranh he nhung ((cong san) or (cong lang)) ((han tai) or (hang tai))*.