A well dressed elderly woman standing in front of a bus decorated with images of purple flowers.
There is a group of boys standing around looking at a sports car.
There can be either a woman or a group of boys who is standing in front of a bus or looking at a car.
There can be either an elderly woman or a group of boys. There can be either a bus or a sports car.
A woman is not the same as a group of boys.  You would not normally stand in front of a bus while looking at a sports car.