Perhaps you should try some spelling variations:
trien hoat » tien hoa
dung land » dung luan, dung lam, dung san
hieu suat » hieu luat, hieu qua
van trien » van tien, va trien, van tren
land van » lang van, lan van, luan van
van hieu » cao hieu
van quan » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( trinh dung land van hieu suat ) or ( binh ((tran quang) or (van quan)) van trien hoat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( trinh dung land van hieu suat ) OR ( binh ((tran quang) OR (van quan)) van trien hoat )).
• Adding a wildcard symbol may retrieve word variants: (( trinh dung land van hieu suat ) or ( binh ((tran quang) or (van quan)) van trien hoat ))*.