Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh vai » hanh vi, hanh va, hanh tai
tang ma » mang may, tang van
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cac toc » cac toi, cac nuoc, cac thoi
hieu ve » hieu va, hieu van
su sach » vu sach
nang ma » sang ma, nang cao, mang may
so sach » so sanh, bo sach, co sach
ve cac » va cac, vien cac
toc va » hoc va, toc ta, tuc va

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: ((su sach) OR (so sach)) ly ((nang ma) OR (tang ma)) hoi. hieu ve cac toc va hanh vai cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sach)) ly ((nang ma) OR (tang ma)) hoi. hieu ve cac toc va hanh vai cua viet~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ly ((nang ma) OR (tang ma)) hoi. hieu ve cac toc va hanh vai cua viet*.