Perhaps you should try some spelling variations:
dang quang » dung quang, nang quan, dang hung
tinh luong » tinh huong, dinh luong, minh luong
luong quan » thong quan, duong qua
dung quan » dung quang, dung luan, dung cua
hieu luat » hieu qua
kiem soat » kiem toan
doi hieu » doi chieu, doc hieu, doi hien
quan va » quan vi, quan ha, luan va
va kiem » van kien

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

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