Perhaps you should try some spelling variations:
tinh thong » tinh thuong, trinh thong, tinh khong
tinh dung » trinh dung, tin dung, tinh quang
hieu luat » hieu qua
quan van » quan luan, quan doan, quang ban
van bien » van tien, van hien, vat bien
quan va » quan vi, quan ha, luan va
bien so » bien doi
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) or (quan va)) hieu luat ) or ( tinh thong quan van bien so ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh dung ((luan van) OR (quan va)) hieu luat ) OR ( tinh thong quan van bien so )).
• Adding a wildcard symbol may retrieve word variants: (( tinh dung ((luan van) or (quan va)) hieu luat ) or ( tinh thong quan van bien so ))*.