Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
xa hanh » xa thanh, xa khanh, va hanh
ban tuc » ban tu, ban tum, ban thuoc
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
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) or (toc sach)) va ((nang ma) or (sang ma)) hoi. hieu van ban tuc xa hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) va ((nang ma) OR (sang ma)) hoi. hieu van ban tuc xa hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) va ((nang ma) or (sang ma)) hoi. hieu van ban tuc xa hanh vai cua tre*.