Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu cac » hieu luc, hieu va, hieu van
cau thuc » cau truc, cuu thuc, can thuc
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cac cau » cac mau, bac cau, ca cau
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang xa hoi. hieu cac cau thuc ((va danh) or (va hanh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. hieu cac cau thuc ((va danh) OR (va hanh)) dai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. hieu cac cau thuc ((va danh) or (va hanh)) dai cua tre*.