Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
cam duc » cam xuc, cao duc, nam duoc
hanh de » hanh ve, hanh kem
cuu tre » cua tre, cau tren, cau treo
de cuu » de cua
x hoi » xa hoi, o hoi, x ho

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) ky nang x hoi. hieu qua ((cam duc) OR (pham duc)) van hanh de cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (toc sach)) ky nang x hoi. hieu qua ((cam duc) OR (pham duc)) van hanh de cuu tre~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky nang x hoi. hieu qua ((cam duc) OR (pham duc)) van hanh de cuu tre*.