Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
thanh tung » thanh cong
tran hoang » tran hong, quan hoang, tran quang
hoc thieu » toc thieu, hoc hien
tung cua » trung cua, tuong cua, dung cua
cong can » cong san, cong dan, cong cau
cong tan » cong tac, cong san, cong thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sang - thanh tung cua cong ((cong can) or (cong tan)) tran hoang~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - thanh tung cua cong ((cong can) OR (cong tan)) tran hoang*.