Perhaps you should try some spelling variations:
luong quan » thong quan, duong qua
tinh luong » tinh huong, dinh luong, minh luong
hieu soat » hieu suat, hieu hoat, hieu luat
kien soat » kiem soat, bien soan, kien hoa
dung lan » dung luan, dung land, dung san
dung lam » dung luan, dung tai, dung dat
van hieu » cao hieu
quan van » luan van, quan va, quan luan
van kien » van tien, van hien, van chien

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tin ((dung lan) OR (dung lam)) van hieu soat ) or ( tinh luong quan van kien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin ((dung lan) OR (dung lam)) van hieu soat ) OR ( tinh luong quan van kien soat )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tin ((dung lan) OR (dung lam)) van hieu soat ) or ( tinh luong quan van kien soat ))".
• Adding a wildcard symbol may retrieve word variants: (( tin ((dung lan) OR (dung lam)) van hieu soat ) or ( tinh luong quan van kien soat ))*.