marble floor cleaning/restoration?

We have black and (http://maplered.com) white Marble (http://www.lightemprador.com) floors in our master bedroom. We had a friend install it and (http://maplered.com) I'm not sure what to use or do to clean it. We have dull spots and (http://maplered.com) scratches already from our two young children. Also they got bath bubbles onto the floor. Has this ruined it?

I've used misc. Marble (http://www.lightemprador.com) cleaners in local stores, but nothing seems to help. I'm wondering now if I might have to resort to having a professional come out and (http://maplered.com) clean or restore it.

We have only been our new home for approx. 6 months. Help!

Thanks!