Perhaps you should try some spelling variations:
tinh dung » trinh dung, tin dung, tinh quang
hieu soat » hieu suat, hieu hoat, kiem soat
hieu luat » hieu qua
dung quan » dung quang, luong quan, dang quang
quan xuan » quang xuan, quan luan, quan quan
xuan kien » xuan dien, xuan kieu, xuan vien
kien soat » kiem soat, bien soan, kien hoa
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: (( tinh dung luan van ((hieu soat) or (hieu luat)) ) or ( tinh dung quan xuan kien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh dung luan van ((hieu soat) OR (hieu luat)) ) OR ( tinh dung quan xuan kien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh dung luan van ((hieu soat) or (hieu luat)) ) or ( tinh dung quan xuan kien soat ))*.