Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
thong cong » trong cong, tong cong, thong thong
hanh tran » hanh trang, thanh tran, hanh tram
cong sach » ong sach, song sach, duong sach
sach toan » hach toan, sach tranh, hoach toan
va thong » va thuong, va phuong, he thong
toan cau » toan cao, toan ban, toan tap
tran va » tran van, trang va, tranh va

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 (chiet tach)) - hanh tran va thong cong sach toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (chiet tach)) - hanh tran va thong cong sach toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (chiet tach)) - hanh tran va thong cong sach toan cau*.