Perhaps you should try some spelling variations:
dung ltan » dung luan, dung tai, dung ngan
dung nhan » dung luan
hieu suat » hieu luat, hieu qua
tinh quan » tinh quang, trinh quan, tin quan
kiem soat » kiem toan
van hieu » cao hieu
van kiem » va kiem, van kien, van hien
luan » lan

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 ltan) OR (dung nhan)) van hieu suat ) or ( tinh quan luan van kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( trinh ((dung ltan) OR (dung nhan)) van hieu suat ) OR ( tinh quan luan van kiem soat )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( trinh ((dung ltan) OR (dung nhan)) van hieu suat ) or ( tinh quan luan van kiem soat ))".
• Adding a wildcard symbol may retrieve word variants: (( trinh ((dung ltan) OR (dung nhan)) van hieu suat ) or ( tinh quan luan van kiem soat ))*.