Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh lap » thanh san, phan lap, thanh hai
hieu ve » hieu va, hieu van
lap cua » lai cua, tap cua, lam cua
cua tre » cua te, cuu tre, cua triet
y sang » _ sang, duy sang
ma hoi » mai hoi, ma hoa, 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: thuoc sach y sang ((ma hoi) OR (xa hoi)). hieu ve ((pham duy) or (pham duc)) gia thanh lap cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y sang ((ma hoi) OR (xa hoi)). hieu ve ((pham duy) OR (pham duc)) gia thanh lap cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y sang ((ma hoi) OR (xa hoi)). hieu ve ((pham duy) or (pham duc)) gia thanh lap cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach y sang ((ma hoi) OR (xa hoi)). hieu ve ((pham duy) or (pham duc)) gia thanh lap cua tre*.