Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
qua hai » qua hoat
hai luc » hai cuc, khai luoc, nhan luc
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cuu tre » cua tre, cau tren, cau treo
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: su sach ky nang x hoi. hieu qua hai luc ((va hanh) OR (va danh)) doi ((cuu tre) OR (cua te))~.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu qua hai luc ((va hanh) or (va danh)) doi ((cuu tre) or (cua te))*.