you must to unlock li mei's village first , you can then find johnny in li mei's village in H8

thanks

I found him but how can I come up with a 13 hit combo with scorpion?

You don't need to use Scorpion and you only need to do at least 12 hits. Just quit and come back and Shujinko will randomly turn to someone else. Unless, you haven't beat Konquest yet than your stuck with the last person you trained with. I don't know a combo for Scorpion since I don't really use him. Liu Kang would probably be the easiest to do a 12 hit combo with. Just do one of his pop-up combos follow by his bicycle kick, such as in pao choi stance 4, 1, 1, U+2, bicycle kick. The bicycle kick adds 8 hits to the 4 hit pop-up combo. If you've not beaten Konquest yet, than train with Li Mei, she is near by, and try this combo with her: in lui he ba fa stance 1, 1, 2, B+1, flip kick, cartwheel kick, flying punches.