Perhaps you should try some spelling variations:
trinh vi » trinh va, trinh ve, trinh viet
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
tinh va » tich va, trinh van, trinh vat
cam cua » ca cua, nam cua, cau cua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
lang ha » long ha
y lang » o lang, _ lang, tay lang
ha hoi » hoa hoi, ha noi, xa hoi

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 y lang ha hoi. ((hieu ve) or (hieu va)) cam cua ban ((trinh vi) or (tinh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y lang ha hoi. ((hieu ve) OR (hieu va)) cam cua ban ((trinh vi) OR (tinh va)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y lang ha hoi. ((hieu ve) or (hieu va)) cam cua ban ((trinh vi) or (tinh va)) cua tre*.