Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
cam duc » cam xuc, cao duc, pham duc
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va
nang xa » lang xa, nang ma, mang xa
cua tre » cua te, cuu tre, cua triet
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 ty ((nang xa) or (nang x)) hoi. ((hieu ve) or (hieu van)) cam duc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (nang x)) hoi. ((hieu ve) OR (hieu van)) cam duc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) or (nang x)) hoi. ((hieu ve) or (hieu van)) cam duc va hanh vi cua tre*.