Can you recommend a product which will improve the tarnished chrome effect trim on the exterior of my car?

Can you recommend a product which will improve the tarnished chrome effect trim on the exterior of a (modern, not classic) vehicle? The 'chrome' has a milky appearance...perhaps oxidisation?

How can I keep chrome trim in good condition?

My Peugeot 2008 has quite a lot of chrome trim - what would be your recommendation to keep this in good condition?