Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hanh lam » thanh lap, hanh kem, hanh va
hanh lai » hanh tai, thanh lap, thanh loi
pham day » phap day, pham duy, pham xay
sach thu » sach thue, sach thieu, sach tham
van pham » san pham, van phan, van phat
thu xang » thu hang, thu bang, thu dang
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, me hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach thu xang ((ma hoi) OR (ma hoa)). hieu van pham day va ((hanh lai) or (hanh lam)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thu xang ((ma hoi) OR (ma hoa)). hieu van pham day va ((hanh lai) OR (hanh lam)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thu xang ((ma hoi) OR (ma hoa)). hieu van pham day va ((hanh lai) or (hanh lam)) cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach thu xang ((ma hoi) OR (ma hoa)). hieu van pham day va ((hanh lai) or (hanh lam)) cua tre*.