Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
thanh trung » thanh tung
thieu dang » thien dang, thieu khang, chieu sang
trung cua » truong cua, trung tuan, trung cap
cua khong » hua khong, cua phuong, cua thuong
cong ban » cong bang, cong tan, cong dan
cong san » cong tac
toan cau » 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 dang) OR (thieu quang)) - thanh trung cua khong ((cong ban) or (cong san)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu dang) OR (thieu quang)) - thanh trung cua khong ((cong ban) OR (cong san)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu dang) OR (thieu quang)) - thanh trung cua khong ((cong ban) or (cong san)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu dang) OR (thieu quang)) - thanh trung cua khong ((cong ban) or (cong san)) toan cau*.