Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van lam » van nam
sach ky » sac ky, sach y, sach ty
su sach » so sach, vu sach
dang ha » dong ha, dung ha, lang ha
dang xa » dang xay, lang xa, dang va
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.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((dang xa) or (dang ha)) hoi. hieu van lam ((duc va) or (tuc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((dang xa) OR (dang ha)) hoi. hieu van lam ((duc va) OR (tuc va)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((dang xa) or (dang ha)) hoi. hieu van lam ((duc va) or (tuc va)) hanh vi cua tre*.