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
tam nhung » tham nhung, cam nhung, nam nhung
cong tan » cong tac, cong san, cong thanh
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu quang)) - thanh trung tam nhung cong tan ((toan cau) OR (toan tap))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) or (thieu quang)) - thanh trung tam nhung cong tan ((toan cau) OR (toan tap))~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (thieu quang)) - thanh trung tam nhung cong tan ((toan cau) OR (toan tap))*.