Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
tu sach » thu sach, su sach, te sach
qua cam » qua cham, qua cac, qua ca
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
hanh de » hanh ve
cua tre » cua te, cuu tre, cua triet
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 van ((hanh de) OR (hanh kem)) cua 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 van ((hanh de) OR (hanh kem)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky nang x hoi. hieu qua cam duc van ((hanh de) OR (hanh kem)) cua tre*.