Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
cac loc » cac lop, cac toc, cac hoc
van cac » van hac, van cau, van bac
cua tre » cua te, cuu tre, cua triet
nang xa » lang xa, nang ma, mang xa
can ky » van ky, ban ky, tan ky
dan ky » van ky
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 ((can ky) or (dan ky)) ((nang xa) OR (nang x)) hoi. hieu van cac loc va thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((can ky) OR (dan ky)) ((nang xa) OR (nang x)) hoi. hieu van cac loc va thanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((can ky) or (dan ky)) ((nang xa) OR (nang x)) hoi. hieu van cac loc va thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((can ky) or (dan ky)) ((nang xa) OR (nang x)) hoi. hieu van cac loc va thanh vi cua tre*.