how was Cherokee different from the other dogs White Fang had fought?

Cherokee kept his distance; he dodged and moved about.

Not that Cherokee was slow.  He could turn and whirl swiftly enough, but White Fang was never there.  Cherokee was puzzled, too.  He had never fought before with a dog with which he could not close.  The desire to close had always been mutual.  But here was a dog that kept at a distance, dancing and dodging here and there and all about.  And when it did get its teeth into him, it did not hold on but let go instantly and darted away again.