Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
va hanh » van hanh, va thanh, va danh
cac dai » cac dan, cac bai, can dai
van cac » van hac, van cau, van bac
sach ky » sach y, sach ty, sach kem
dai hoi » dai hoc, dai hai, dai moi
dai va » mai va
vi cua » vai cua, di cua
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky

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 ky) OR (sac ky)) nang ((ma hoi) OR (dai hoi)). hieu van cac dai va hanh vi cua vat~.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang ((ma hoi) or (dai hoi)). hieu van cac dai va hanh vi cua vat*.