Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
trung tuan » trung thanh, trung tam, tran tuan
tung tuan » hung tuan, quang tuan, trang tuan
cong sang » cong lang, cong vang, cong bang
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: theo chieu sach - thanh ((tung tuan) OR (trung tuan)) nhung ((cong san) or (cong sang)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - thanh ((tung tuan) OR (trung tuan)) nhung ((cong san) OR (cong sang)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sach - thanh ((tung tuan) OR (trung tuan)) nhung ((cong san) or (cong sang)) toan cau".
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - thanh ((tung tuan) OR (trung tuan)) nhung ((cong san) or (cong sang)) toan cau*.