Kiba can tell the difference. He doesn't really know how or why, but he can. There's something in the way the puppet moves that is so different from the master. The way the wood moves and the way Kankuro does is obvious only to Kiba, even though Kankuro does his best to mimic his puppet's jerky movements. The difference between being the wood and understanding the wood. His face on the puppet fools allies and enemies, just like it is meant to. But it doesn't fool Kiba.
It doesn't have anything to do with scent because, as Kiba hates to admit, the puppets smell exactly like Kankuro. Woodwork and poison and paint. But somehow he can tell, better then Neji or Hinata, with their bloodlimit. He doesn't need a special technique, or more accurately he already has one…
No one has really found a word for it. At least not a human word. It's not something that humans do. It's that something that only a dog could understand. After all, as his sister says, a dog always knows his master. And they both knew that if Kankuro called Kiba would come running.