Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
cua rang » cua dang, cua hang, cua lang
qua dung » quang dung, su dung, qua song
cong tac » cong ty
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: ho ((hieu lang) or (chieu sach)) - thanh trung ((cua rang) or (qua dung)) cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (chieu sach)) - thanh trung ((cua rang) OR (qua dung)) cong tac toan cau.
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) or (chieu sach)) - thanh trung ((cua rang) or (qua dung)) cong tac toan cau*.