Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
va hanh » van hanh, va thanh, va danh
cac tuc » cac toc, cac tu, cac tac
van cac » van hac, van cau, van bac
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
so sanh » do sanh
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
vi cua » vai cua, di cua

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: ((su sach) OR (so sanh)) va ((nang xa) OR (lang xa)) hoi. hieu van cac tuc va hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sanh)) va ((nang xa) OR (lang xa)) hoi. hieu van cac tuc va hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) va ((nang xa) OR (lang xa)) hoi. hieu van cac tuc va hanh vi cua tre*.