Perhaps you should try some spelling variations:
chuan quoc » cua quoc, phan quoc, chua nuoc
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
hieu ve » hieu va, hieu van
va hanh » va thanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
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: toc sach y nang x hoi. hieu ve ((chuan quoc) OR (han quoc)) ((va hanh) OR (van hanh)) dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang x hoi. hieu ve ((chuan quoc) or (han quoc)) ((va hanh) OR (van hanh)) dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang x hoi. hieu ve ((chuan quoc) or (han quoc)) ((va hanh) OR (van hanh)) dai cua tre*.