Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va
va hanh » va thanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet
ca cua » co cua
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ky nang x hoi. ((hieu ve) or (hieu van)) nam thuc ((va hanh) OR (van hanh)) ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky nang x hoi. ((hieu ve) OR (hieu van)) nam thuc ((va hanh) OR (van hanh)) ca cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky nang x hoi. ((hieu ve) or (hieu van)) nam thuc ((va hanh) OR (van hanh)) ca cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky nang x hoi. ((hieu ve) or (hieu van)) nam thuc ((va hanh) OR (van hanh)) ca cua tre*.