Perhaps you should try some spelling variations:
sang tao » hang tai
su sach » vu sach
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
sang ma » tang ma, nang ma, mang may
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
va bao » va bai
bao so » bai so, bao co, bao ho
va cua » va chua, via cua, ca cua
so va » so van, so vat, su va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (so sach)) ky ((sang ma) or (sang tao)) hoi. hieu va bao so va hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky ((sang ma) OR (sang tao)) hoi. hieu va bao so va hanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) ky ((sang ma) or (sang tao)) hoi. hieu va bao so va hanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (so sach)) ky ((sang ma) or (sang tao)) hoi. hieu va bao so va hanh va cua tre*.