[troubler]

Actually I want to perform following two tasks:

1) I want to become social media investigator! I heard that using maltego, you can perfom all this kind of things & many more but I was not able to find any in depth tutorials on it!

2) I just got article that someone just found 1m passports left over internet & found using elastic search!! So I just wann know how they do it..

Please give me any advise that what will be the essential to understand above things.