Perhaps you should try some spelling variations:
qua nhan » cua nhan, qua nhat, qua phan
nhan duc » nhan duoc, nhan luc, phan duc
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
va hanh » van hanh, va thanh, va danh
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
va dan » ca dan, va dao, va dau

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: su sach y nang ma hoi. hieu qua nhan duc ((va hanh) OR (va dan)) doi cua tre~.
• Adding a wildcard symbol may retrieve word variants: su sach y nang ma hoi. hieu qua nhan duc ((va hanh) or (va dan)) doi cua tre*.