Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
va hanh » van hanh, va thanh, va danh
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
ve cau » ke cau, va cau, ve cac
vi cau » va cau, di cau, viet cau
tu cam » tu cham, tu cac, tu nam
cam ky » cao ky, cac ky
ma hoi » xa hoi, ma hoa, me hoi
ve nam » he nam, va nam, le nam

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 cam ky nang ((ma hoi) OR (mai hoi)). hieu ve nam thuc va hanh ((vi cau) OR (ve cau)) tren~.
• Adding a wildcard symbol may retrieve word variants: tu cam ky nang ((ma hoi) or (mai hoi)). hieu ve nam thuc va hanh ((vi cau) or (ve cau)) tren*.