Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
thuc va » thuc vat, thuc day
van cac » van hac, van cau, van bac
so sanh » do sanh
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang
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) or (so sanh)) v nang xa hoi. hieu van cac ((thuc va) or (thuc dan)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sanh)) v nang xa hoi. hieu van cac ((thuc va) OR (thuc dan)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) v nang xa hoi. hieu van cac ((thuc va) or (thuc dan)) hanh vi cua tre*.