A lot of people say it can sense cars quite well. Maybe because they are hotter and larger and thus can be sensed further away. The spec probably only applies to people.
The only thing I can recommend is to mount the sensor in such a way so that it has no line-of-sight to the street. Higher up on the wall if there is an overhang that can block the street. Or 90 degrees from the front door so it isn’t facing the street. I saw one person mount it basically upside-down on the patio ceiling (back straight up, with logo towards the street) so the down angle was facing the door.
The idea is to get the street out of its sight.