Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
trung va » truong va, trang va, trung ha
hieu van » hieu va, thien van, lieu va
van chat » cao chat
vai cua » dai cua, hai cua, lai cua
truc va » thuc va, thuc vat
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky

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) or (sac ky)) nang xa hoi. hieu van chat ((truc va) OR (trung va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sac ky)) nang xa hoi. hieu van chat ((truc va) OR (trung va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sac ky)) nang xa hoi. hieu van chat ((truc va) OR (trung va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sac ky)) nang xa hoi. hieu van chat ((truc va) OR (trung va)) hanh vai cua tre*.