Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thanh trung » thanh tung
thieu sang » chieu sang, thieu khang, hieu lang
nhung cong » dung cong, thong cong, hang cong
thanh chau » thanh cha, thanh cham, thanh chu
trung cua » truong cua, trung tuan, trung cap
cua nhung » va nhung
cong tac » cong ty
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: hoc ((thieu sang) OR (thieu quang)) - thanh trung cua nhung cong tac ((thanh chau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu quang)) - thanh trung cua nhung cong tac ((thanh chau) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (thieu quang)) - thanh trung cua nhung cong tac ((thanh chau) or (toan cao))".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (thieu quang)) - thanh trung cua nhung cong tac ((thanh chau) or (toan cao))*.