Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu xanh
chieu sang » chieu xanh, hieu lang, nhieu tang
hanh tranh » canh tranh, hanh trinh, hanh trang
tranh cua » doanh cua, manh cua
bang cong » dang cong, bang song, hang cong
cua bang » chua bang, cua ban, cua dang
cong van » cong vang, cong san, song van
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sach) or (chieu sang)) - hanh tranh cua bang cong van ((toan cau) OR (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (chieu sang)) - hanh tranh cua bang cong van ((toan cau) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) or (chieu sang)) - hanh tranh cua bang cong van ((toan cau) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (chieu sang)) - hanh tranh cua bang cong van ((toan cau) OR (toan tap))*.