Perhaps you should try some spelling variations:
hanh lam » thanh lap, hanh va, dinh lam
so sach » so sanh, bo sach, co sach
ty tang » tay tang, ty hang, ky tang
hieu vu » hieu va, hieu ve, hieu su
vu pham » su pham, vi pham, vu kham
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

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

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