Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
trinh toan » tinh toan, trinh han, trinh quan
anh quang » anh xquang, anh quan, nhanh quang
doi chieu » doc hieu, ho chieu, mot chieu
quan dung » quang dung, quan duong, qua dung
dung cong » dung trong
toan tap » toan ban
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (doi chi)) sang - ((anh quang) or (thanh toan)) quan dung cong trinh toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doi chi)) sang - ((anh quang) OR (thanh toan)) quan dung cong trinh toan tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doi chi)) sang - ((anh quang) or (thanh toan)) quan dung cong trinh toan tap*".