Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
trung cua » truong cua, trung tuan, trung cap
hang cong » dang cong, bang cong, thanh cong
hang nong » thang long, han tong
tac toan » tap toan, tam toan, hach toan
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: doi ((chieu sang) OR (chieu sach)) - thanh trung cua ((hang cong) or (hang nong)) tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu sang) OR (chieu sach)) - thanh trung cua ((hang cong) OR (hang nong)) tac toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sang) OR (chieu sach)) - thanh trung cua ((hang cong) or (hang nong)) tac toan cau".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu sang) OR (chieu sach)) - thanh trung cua ((hang cong) or (hang nong)) tac toan cau*.