Sites like , Chegg , and Stack Exchange often have step-by-step breakdowns of the more famous problems in the book. These are often better than the PDF manuals because they explain the logic behind the steps. How to Use a Solutions PDF Without "Cheating Yourself"
If you are looking for a description or a "write-up" to accompany a PDF of the solutions for Vector Calculus Marsden Tromba Vector Calculus Solutions Pdf