Where Can I find New Hissatsu Technique And Can We Buy Hissatsu Technique like inazuma eleven DS??

to find new hissatsu technique Should be your relationship with another player became a full example, if gazell and burn Their relationship has become full you can perform the technique fire billzard
There is another way is to buy another level of the same player, for example if you have endou in raimon you can buy endou in inazuma japan and you will get new technnique