Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh via » hanh va, anh va, hanh ve
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
qua hai » qua hoat
cuu tre » cua tre, cau tren, cau treo
hai so » dai so, tai so, thai son
so va » so van, so vat, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang cao hoi. hieu qua hai so va ((hanh via) or (hanh vi)) ((cua triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang cao hoi. hieu qua hai so va ((hanh via) OR (hanh vi)) ((cua triet) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: so sach ky nang cao hoi. hieu qua hai so va ((hanh via) or (hanh vi)) ((cua triet) or (cuu tre))*.