I am SO sorry that it took me this long to reply, but my computer broke down! I did ask my teacher about suggestions, and she said that you have to introduce the dog to the different situations very slowly! First you have get him used to the scent of cars, and have one drive by slowly, etc. With the people, take him in small crowds and work your way up...She also said that every dog is different, so, it might not work for yours and she wishes you the best of luck!
I'm really sorry!