So here some books I selected for you according to Sketching (how to start to sketch a car or a product), Rendering & Illustration techniques.
Car Design Sketching Tips by Luciano Bove this is my book made to give you a real reference guide step by step to learn sketching cars from basics of drawing to great perspective drawings.
49 pages illustrated by me easy to understand and follow to exercise at home. You should check it!
To me this book is a must to have!
This book is important because shows how to use perspective and drawing basic techniques to draw simple and complex shapes. In this book also first rules to use color like simple shadings and markers.
The author Matt Marrocco is a professional designer very famous on the net specially on Facebook look for him on FB, too!
This is the book in which you will discover the science fiction art & design world with lots of car designs, very exciting book super well done and a great guide for those addicted to digital art.
For example all students of engineering universities dreaming to go for a Transportation Design Master after their University.
With the right book and a lot of exercise you can catch up and improve.