Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
sang ma » tang ma, nang ma, sang tao
va cham » va chat, va tham
danh vi » hanh vi, danh di, danh va
dinh vi » dinh ve, dinh viet, dinh tri
cua tre » cua te, cuu tre, cua triet
y sang » _ sang, duy sang
ma hoi » mai hoi, xa hoi, ma hoa
soc va » hoc va, loc va, doc va

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) or (thu sach)) y sang ma hoi. lieu va cham soc va ((danh vi) OR (dinh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y sang ma hoi. lieu va cham soc va ((danh vi) OR (dinh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) y sang ma hoi. lieu va cham soc va ((danh vi) OR (dinh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) y sang ma hoi. lieu va cham soc va ((danh vi) OR (dinh vi)) cua tre*.