Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
chieu sach » chinh sach, chiet tach, chieu sang
nhung cong » dung cong, thong cong, hang cong
quang ma » xquang ma, quang va, quang manh
ma nhung » va nhung, a nhung, la nhung
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: theo ((chieu tinh) or (chieu sach)) - nhanh quang ma nhung cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu tinh) OR (chieu sach)) - nhanh quang ma nhung cong tac toan cau.
• Adding a wildcard symbol may retrieve word variants: theo ((chieu tinh) or (chieu sach)) - nhanh quang ma nhung cong tac toan cau*.