Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh lai » hanh lam, hanh tai, thanh lap
lai cua » dai cua, hai cua, lai chau
ve cham » va cham, ve chat, vu cham
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
ma hoi » xa hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky sang ((ma hoi) OR (mai hoi)). hieu ve cham ((xuc va) or (thuc vat)) hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky sang ((ma hoi) OR (mai hoi)). hieu ve cham ((xuc va) OR (thuc vat)) hanh lai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky sang ((ma hoi) OR (mai hoi)). hieu ve cham ((xuc va) or (thuc vat)) hanh lai cua tre*".