Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
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 di » hanh de, hang di, danh di
cua te » cua tu
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 (hoc sach)) ky nang x hoi. hieu qua cam duc van ((hanh di) OR (hanh vi)) cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (hoc sach)) ky nang x hoi. hieu qua cam duc van ((hanh di) OR (hanh vi)) cua te~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (hoc sach)) ky nang x hoi. hieu qua cam duc van ((hanh di) OR (hanh vi)) cua te*.