Removing paint stains

Let's face it that we all try our best to keep out cars clean, shinny, and as well protected. Unfortunately we cannot always cover our cars and as well protect it from everything. I been noticing that everytime I was my car and my brothers I tend to see some stains when I look at it from an angle. It looks like it was caused from bird droppings or some other factor. Does anyone got a technique or recommend a product in where I can remove them? Can I use a cutting compound (such as a V36 and V38 polisher) to remoce them?