Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
hanh vai » hanh vi, hanh va, hanh tai
thuc dan » thuc hanh, hoc dan, thuc vat
vai cua » dai cua, hai cua, lai cua
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc day
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet

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 _ lang xa hoi. ((hieu van) or (hieu va)) cau ((thuc va) or (thuc dan)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach _ lang xa hoi. ((hieu van) OR (hieu va)) cau ((thuc va) OR (thuc dan)) hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach _ lang xa hoi. ((hieu van) or (hieu va)) cau ((thuc va) or (thuc dan)) hanh vai cua tre*.