Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
hanh vai » hanh vi, hanh va, hanh tai
sach thu » sach thieu, sach tham, cach thuc
vai cuu » vai cua
va hanh » van hanh, va thanh, va danh
chat do » chat deo, chat doc, chat co
ve chat » va chat, van chat
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
co hoi » co hoc
do va » do van, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach thu) or (sach thue)) nang ((co hoi) OR (co loi)). hieu ve chat do va hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach thu) OR (sach thue)) nang ((co hoi) OR (co loi)). hieu ve chat do va hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach thu) or (sach thue)) nang ((co hoi) OR (co loi)). hieu ve chat do va hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach thu) or (sach thue)) nang ((co hoi) OR (co loi)). hieu ve chat do va hanh vai cuu tre*.