What are the plans of Nimzo Indian defence

I know what the nimzo-Indian defence is but I would like to know what the plans in the middle games are.

With this you would have to be more specific.  There is no "catch-all" plan in the Nimzo.  With mobile pawns and numerous variations that White can play, no two being the same, unlike say, the French, where all lines except the exchange it's about attacking d4, not the case here!

There are blockading ideas in some lines, breaking of the center and going for the White King in many lines where Kingside Development is extremely slow, and there are lines where White's pawn structure dictates that Black wants to reach a minor piece ending, ideally Knight vs White's dark-Squared Bishop and then attack c4.

Could you be more elaborate with each plan and tell me some lines please.

Twenty dollars for an e-book!? Ouch.

Some general ideas are:

1) since black has exchanged the dark squared bishop, he wants to place his central pawns on dark squares--so a central pawn formation of d6-e5 is usually a good plan.

2) If black succeeds in disrupting white's pawn structure with the dark squared bishop exchange, the squares c3 and c4 are often weak spots that black works to exploit.  

The wiki-pedia articles on most openings are actually somewhat decent overviews.

https://en.wikipedia.org/wiki/Nimzo-Indian_Defence

This game is typically considered instructive in the Nimzo-Indian. Black gets control over the central light squares because there isn't a knight on c3 to cover them. Black has to counter white's center though.