Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sang » chieu sang, thieu khang, thieu quang
thong cong » trong cong, tong cong, thong thong
trung cap » truong cao, trung tam
hang cong » dang cong, hang nong, bang cong
tac khan » tac nhan, cac khoan, tac chuan
khan cap » khan ap, than cap, khoan cam

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 cap ((thong cong) or (hang cong)) tac khan cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu sang - thanh trung cap ((thong cong) OR (hang cong)) tac khan cap.
• Adding a wildcard symbol may retrieve word variants: toc thieu sang - thanh trung cap ((thong cong) or (hang cong)) tac khan cap*.