Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
tieu sach » dien sach, te sach, viet sach
tranh kha » tranh ha, tranh chap, trinh khai
kha nang » phap nang, ky nang, ki nang
song tan » song than, song van, cong tan
toan cau » toan ban, toan tap, toan tai
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 ((tieu sach) or (chieu sach)) - canh tranh kha nang song tan ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((tieu sach) OR (chieu sach)) - canh tranh kha nang song tan ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: theo ((tieu sach) or (chieu sach)) - canh tranh kha nang song tan ((toan cau) or (toan cao))*.