Perhaps you should try some spelling variations:
kho tang » cao tang
so sach » so sanh, bo sach, co sach
hanh de » hanh ve, hanh kem
thuc va » thuc dan, thuc day
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, ky trong
ma hoi » mai hoi, xa hoi, ma hoa
ve nam » he nam, va nam, le nam
de cua » le cua, te cua, dieu cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((ky tang) OR (kho tang)) ma hoi. hieu ve nam ((thuc va) OR (thuc vat)) hanh de cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((ky tang) OR (kho tang)) ma hoi. hieu ve nam ((thuc va) or (thuc vat)) hanh de cua vat~".
• Adding a wildcard symbol may retrieve word variants: so sach ((ky tang) OR (kho tang)) ma hoi. hieu ve nam ((thuc va) or (thuc vat)) hanh de cua vat*.