Perhaps you should try some spelling variations:
luong luan » luong quan, luong xuan, luong quang
cuong luan » cuong quan, cong luan, truong luan
quang tang » quang thang, quang dang, quang tung
hieu soat » hieu suat, hieu hoat, hieu luat
kiem soat » kiem toan
van hieu » cao hieu
tang van » dang van, hoang van, trong van
van kiem » va kiem, van kien, van hien

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

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