Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hieu van » thien van, lieu va, hieu ve
sach lo » sach dao, sach doi, sach hoi
nang ma » tang ma, sang ma, nang cao
sach ho » sach hoi, sach ha, sach dao
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh de » hanh ve, hanh kem
ma hoi » mai hoi, xa hoi, ma hoa
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: tu ((sach ho) OR (sach lo)) nang ma hoi. ((hieu van) OR (hieu va)) am thuc va hanh de cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ho) OR (sach lo)) nang ma hoi. ((hieu van) or (hieu va)) am thuc va hanh de cua viet~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ho) OR (sach lo)) nang ma hoi. ((hieu van) or (hieu va)) am thuc va hanh de cua viet*.