Perhaps you should try some spelling variations:
dinh quang » tinh quang, minh quang, dinh duong
quang luan » quan luan, quang tuan, quang uan
hieu soat » hieu suat, hieu hoat, kiem soat
hieu luat » hieu qua
tin nang » tin dung, ki nang, thi nang
nang sua » nang suat, nang dua, nang cua
doi bien » doi dien, voi bien, doi hien
bien so » bien doi

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( dinh quang luan van ((hieu soat) or (hieu luat)) ) or ( tin nang sua doi bien so ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( dinh quang luan van ((hieu soat) OR (hieu luat)) ) OR ( tin nang sua doi bien so )).
• Adding a wildcard symbol may retrieve word variants: (( dinh quang luan van ((hieu soat) or (hieu luat)) ) or ( tin nang sua doi bien so ))*.