Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cac dat » cac dan, cai dat, cac dai
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang x ho. ((hieu ve) or (hieu hien)) cac dat va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang x ho. ((hieu ve) OR (hieu hien)) cac dat va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x ho. ((hieu ve) or (hieu hien)) cac dat va hanh vi cua tre*.