Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
sach dao » lanh dao
cham duc » pham duc, cham soc, pham duy
sach duy » sach dung, sach duoc, sach dat
va hanh » van hanh, va thanh, va danh
va cham » va chat, va tham
hieu va » lieu va, hieu qua
nang ma » tang ma, nang cao, mang may
cua tre » cua te, cuu tre, cua triet
sang ma » tang ma, sang tao, mang may

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) or (sach dao)) ((sang ma) OR (nang ma)) hoi. hieu va cham duc va hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach duy) OR (sach dao)) ((sang ma) OR (nang ma)) hoi. hieu va cham duc va hanh dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach duy) or (sach dao)) ((sang ma) OR (nang ma)) hoi. hieu va cham duc va hanh dai cua tre*".