Ein was very fussy when he was a puppy and only ate one meal a day (and it took him all day of picking at it to eat it). Ever since the day he came back from getting neutered, he's had a major "starving puppy" act and wants to eat constantly.
But if your guy USED to eat and doesn't anymore, I'd get him checked out, just be to sure nothing is wrong that is causing his recent lack of appetite. Adding the "lil bits" Greenies or rice krispies to the top of his dish sometimes helped Ein to eat when he was being fussy, but not always. Also, adding the least little bit of water to dry food made him happy. Just enough to soften it and moisten it. But if your pup won't eat wet food, then that may not work. I'd give the Greenies a try, though. I've heard tons of people say that their dogs were addicted to Greenies.