Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
van cac » van hac, van cau, van bac
cac loc » cac lop, cac toc, cac hoc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
loc va » hoc va, luc va
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 cac ky ((nang xa) or (lang xa)) hoi. hieu van cac loc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky ((nang xa) OR (lang xa)) hoi. hieu van cac loc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu cac ky ((nang xa) or (lang xa)) hoi. hieu van cac loc va hanh vi cua tre*.