Perhaps you should try some spelling variations:
sach duy » sach dung, sach duoc, sach dao
danh lai » danh sai, gianh lai, dinh lam
cham duc » pham duc, cham soc, pham duy
tu sach » thu sach, su sach, te sach
lai cua » dai cua, hai cua, lai chau
va danh » va dinh, va dan, va hanh
hieu va » lieu va
sang ma » nang ma, sang tao, mang may
tang ma » mang may, tang 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 duy ((sang ma) or (tang ma)) hoi. ((hieu va) OR (hieu qua)) cham duc va danh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach duy ((sang ma) OR (tang ma)) hoi. ((hieu va) OR (hieu qua)) cham duc va danh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach duy ((sang ma) or (tang ma)) hoi. ((hieu va) OR (hieu qua)) cham duc va danh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach duy ((sang ma) or (tang ma)) hoi. ((hieu va) OR (hieu qua)) cham duc va danh lai cua tre*.