Everytime you drive your car afterwards a slight burning smell comes from the bonnet does anybody know what this could be?

Everytime you drive your car afterwards a slight burning smell comes from the bonnet does anybody know what this could be?
could be oil leaking from the engine.could be oil around the engine while the mechanic was filling the engine with oil. could be a plastic cable burning on the hot engine.could also be the smell of a cleaning product you use on your engine.might be an animal trapped inside your hood. could be antifreeze on your engine.you can also pop the hood and see :)