There are a lot of different hamster foods on the market, but each and every one of them are very different in terms of ingredients. It's hard to get the right nutritional values for your hamster in just one package. Therefore, I mix my own hamster food by combining different commercial brands to get the right ingredients. These are the ones I'm currently using:
Left to right, top: MultiFit Hamster, Supreme Science Selective hamster, sunflower seeds
Left to right, bottom: Vilmie (rabbit and guineapig), JR Farm Dwarf hamster mix
For Pixie, my Syrian hamster, I use all of these but the dwarf hamster mix. I also like to add a few dog treats and sometimes dried banana or carrot flakes for treats. She used to get Harry Hamster, but I can't buy that brand here in Denmark and it got too annoying having to order the food every time. She still has some Harry Hamster mixed into her food mix though.
For Kiwi and Mango, my campbell dwarves, I mix all of the foods in the picture, plus a few dog treats. The MultiFit mix contains dried mealworms, and the JR Farm mix contains proteins from chicken, beef and shrimps. Though I tend to remove most pieces of corn, carrot or peas from their food to avoid too much sugar.
Both breeds get fresh vegetables or herbs at times, plus some other kind of protein source, such as boiled egg or some meat. I'm not one of those people who give vegetables everyday, but I will try to do it more often since the hamsters like it so much. :)