Perhaps you should try some spelling variations:
quang quan » quang tuan, quan quan, quang xuan
tinh dang » tinh dung, binh dang, tinh sang
dang quan » dang quang, nang quan, dung quan
hieu suat » hieu luat, hieu qua
quang uan » quang tuan, quang ban, quang tran
kiem soat » kiem toan
quan van » luan van, quan va, quan luan
van hieu » cao hieu
va kiem » van kien

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tinh dang quan van hieu suat ) or ( tinh ((quang quan) or (quang uan)) va kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh dang quan van hieu suat ) OR ( tinh ((quang quan) OR (quang uan)) va kiem soat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh dang quan van hieu suat ) or ( tinh ((quang quan) or (quang uan)) va kiem soat ))*.