Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thai ky » than ky, thai ly, thao ky
thoi ky » hoi ky
nang xa » nang x, lang xa, nang ma
dinh vi » dinh ve, dinh viet, dinh tri
cua tre » cua te, cuu tre, cua triet
xuc va » tuc va, luc va, xac 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: te ((thai ky) or (thoi ky)) nang xa hoi. hieu van nam ((xuc va) OR (duc va)) dinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((thai ky) OR (thoi ky)) nang xa hoi. hieu van nam ((xuc va) OR (duc va)) dinh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((thai ky) or (thoi ky)) nang xa hoi. hieu van nam ((xuc va) OR (duc va)) dinh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((thai ky) or (thoi ky)) nang xa hoi. hieu van nam ((xuc va) OR (duc va)) dinh vi cua tre*.