Here are some pics that might help you:
Campbell's Dwarf Hamster:
Winter White Hamster:
Chinese hamster (and I'm guessing this is what you have...)
Another pic of it (taken from http://www.midlandhamsterclub.co.uk/...r/chinese.html
Campbell's, Winter Whites, Roborovski and Chinese are often referede to as "dwarf hamsters" but they are 4 different species. If you have two of different species, I suggest that you separate them as you should NEVER mix different species of rodents. If you have a hamster and another species, like a mouse or a gerbil, separate them as well. Notice that they all have pretty different features, like furry tail in gerbils, naked tail in mice, short tail in hamsters, big ears in mice, big almond eyes in gerbils... ect.
Even though dwarf hamsters are somewhat social, they are very territorial too. On the experience I've had, you can only put 2 dwarves together if they are young. Once they are adults, it would be hard/impossible to put them together. If you indeed have 2 of the same species, and have a male and a female, think about the babies they will have if you put them together. They have an average of 6 babies per litter... can have a lot more, and the female will get pregnant the same day she gives birth, so she can have around 10-11 litters per year.
Good luck with them, let us know what you conclude with the information I've given you, and, if you can, post pictures, as I would love to see them. 8) If you need any more help or tips, don't be afraid to ask! 8)