Hi mahtab. first point please either call me hamedkvs.ir or hamed ;).
the second point about your reply: Yes I am aware of the difference, hence we can say that every car is a vehicle too, but not every vehicle is a car.
According to Longman Dictionary of Contemporary English:
1 [formal] a machine with an engine that is used to take people or things from one place to another, such as a car, bus, or truck: motor vehicle
--a description of the stolen vehicle
--Have you locked your vehicle?
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but if your question is why I chose "vehicle" over "car", I can say I thought at the moment that maybe by "ماشین" he/she means a bus, a truck or something like that.
Overall I don't agree my sentence is wrong nor I think there's anything wrong with yours. I think both convey the same meaning, although mine has a broader application.