Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
ban benh » san benh, ba benh, can benh
ban banh » ban hanh, ban anh, ban danh
ky lang » ky dang, ky tang, tay lang
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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: thu sach ((ky lang) OR (ky nang)) xa hoi. hieu van cam duc ((ban benh) OR (ban banh)) di cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ky lang) OR (ky nang)) xa hoi. hieu van cam duc ((ban benh) or (ban banh)) di cua tre~".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky lang) OR (ky nang)) xa hoi. hieu van cam duc ((ban benh) or (ban banh)) di cua tre*.