So your e-cig came in a generic package that only said "create healthy life"?
I googled the above phrase and was directed overwhelmingly to the alibaba website. Many of the devices pictured were eGO style 510 threaded devices, but I can't be certain this is what you have.
How did you come to the conclusion of the possible kr808 format?
Perhaps you could take a picture from your cell phone or maybe a webcam? That would help tremendously I think. Try and focus on the connector its self, such as a close up of the threads on both the cartomizer and the battery.
To answer your question, it is possible to refill cartomizers with aftermarket
juice. Keep in mind that the original flavor of the cartomizer will still remain for a while if you put a different flavor inside. It just won't be nearly as strong, so try and stick with a similar flavor.
You can also buy blank cartomizers, but to be sure you order the right ones, you need to know exactly what type of connection you have.