Perhaps you should try some spelling variations:
dau tieng » dau tien, cau tieng, day tieng
ve cham » va cham, ve chat, vu cham
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
mai hoi » mai khoi, dai hoi, lai hoi
vi dau » vi dai, va dau, bi dau
tu cam » tu cham, tu cac, tu nam
cam ky » cao ky, cac ky
ma hoi » xa hoi, ma hoa, me hoi
ve cam » ve cac, va cam, ve cai

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 cam) OR (ve cham)) thuc va hanh vi dau tieng~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cam ky nang ((ma hoi) or (mai hoi)). hieu ((ve cam) OR (ve cham)) thuc va hanh vi dau tieng~".
• Adding a wildcard symbol may retrieve word variants: tu cam ky nang ((ma hoi) or (mai hoi)). hieu ((ve cam) OR (ve cham)) thuc va hanh vi dau tieng*.