I had the same problem with my girls when they were little ...just refused to eat anything!!! Are you feeding premium food?
If you have a feed and grain store near you..or a pet specialty shop..many times they offer free samples of premium dog foods...you could try to obtain free samples...see if your baby likes any of those...My picky eaters really liked Canadai...they are on Natural balance now..and LOVE it...Others swear by Blue Buffalo..and Taste of the wild...you could try mixing a little wet with your dry...see if that helps interest your little one a bit more..
This link tells you how the food you are feeding ranks out of 5 stars...check it out.
Dog Food Ratings by Brand