Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sang » chieu sang, thieu khang, thieu quang
quang dung » quang trung, ung dung, cuong dung
cua dung » cua dang, cua dong, qua dung
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc thieu sang - thanh trung ((cua dung) or (quang dung)) cong tan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu sang - thanh trung ((cua dung) OR (quang dung)) cong tan toan cao.
• Adding a wildcard symbol may retrieve word variants: toc thieu sang - thanh trung ((cua dung) or (quang dung)) cong tan toan cao*.