Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
nhung cong » dung cong, thong cong, hang cong
hanh tang » hanh trang, anh tang, hanh mang
cua nhung » va nhung
tang cua » mang cua, hang cua, tang luan
ty toan » tap toan, huy toan, tam toan
ly toan » le toan, ly hoan, ly tran

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 sang) or (chieu sach)) - hanh tang cua nhung cong ((ty toan) OR (ly toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu sach)) - hanh tang cua nhung cong ((ty toan) OR (ly toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (chieu sach)) - hanh tang cua nhung cong ((ty toan) OR (ly toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu sach)) - hanh tang cua nhung cong ((ty toan) OR (ly toan)) cao*.