A vehicle including a housing. The housing includes an outer portion, an inner portion, an air-flow channel, a plurality of air inlets, an air outlet, and a spoiler surface or a spoiler. The air-flow channel is disposed between the outer portion and the inner portion of the housing. The air inlets are disposed on the outer portion of the housing, and the air outlet is disposed at a rear of the outer portion of the housing. The air-flow channel communicates with the air inlets and the air outlet. The spoiler surface or the spoiler is disposed on a bottom of the outer portion of the housing, a top of the inner portion of the housing, or both the bottom of the outer portion and the top of the inner portion of the housing, for extending path of the air.