Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
thanh tung » thanh cong
ca trong » cad trong, co trong, va trong
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap
tinh » trinh, dinh, minh

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: ho ((trieu tinh) OR (chieu sach)) - thanh tung ((ca trong) OR (cay trong)) cong tac toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((trieu tinh) or (chieu sach)) - thanh tung ((ca trong) OR (cay trong)) cong tac toan cau~".
• Adding a wildcard symbol may retrieve word variants: ho ((trieu tinh) or (chieu sach)) - thanh tung ((ca trong) OR (cay trong)) cong tac toan cau*.