Perhaps you should try some spelling variations:
trinh dang » trinh dung, trinh dan, trinh bang
dung quan » dung quang, dung luan, luong quan
hieu soat » hieu suat, hieu hoat, hieu luat
cong tuan » cong tan, cong thanh, cong quang
cong luan » tong luan, dong luan, cong luong
kien soat » kiem soat, bien soan, kien hoa
quan va » quan vi, quan ha, luan va
va hieu » van hieu, va dieu, va hien
tin » tinh

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 quan va hieu soat ) or ( trinh dang ((cong tuan) or (cong luan)) kien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quan va hieu soat ) OR ( trinh dang ((cong tuan) OR (cong luan)) kien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung quan va hieu soat ) or ( trinh dang ((cong tuan) or (cong luan)) kien soat ))*.