According to Eastern Orthodoxy, is googling the serial numbers of a software and using cracks a sin? I was raised in a little bit poor country where it's almost impossible for individuals to make online payments. No PayPal, Credit cards are for national use only and international use is very expensive. 

When I first started using computers, I used to hack or crack all the software that I use starting from the serial number or the activation of windows to the serial numbers of the photoshop, office, and even the smallest software.

I've never done an online payment to buy any software because it's very expensive to buy them. I just checked the price of 3D max out of curiosity and it costs about $1,500 per year! That means I should work for a whole year without eating or spending any money to buy it. On top of that, I need to buy windows to be able to run it with an additional few months of working without eating.

I know that all the reasons above are not an excuse to steal. But is cracking software and googling their serial numbers considered a sin? Has the Orthodox Church made any known pronouncements on this subject?

I'm Orthodox so I prefer the answer to be from an orthodox point of view.
Again, I am of the mindset that you should seek the advice of a spiritual father in your specific situation, but here is an official statement.

"The Bases of the Social Concept of the Russian Orthodox Church", adopted at the Sacred Bishops' Council of the Russian Orthodox Church, § VII(3), elaborates on intellectual property, specifically stating: 


  The Church recognises the existence of various forms of ownership.... 
  
  The intellectual property, such as scientific works and inventions, information technologies, works of art and other achievements of the creative thought acquires a growing significance. The Church welcomes the creative work aimed at benefitting society, and deplores the violation of copyright.


There are even examples where monasteries in the Russian Orthodox Church (albeit ROCOR in the linked example, but this distinction is no longer relevant) have taken legal action to protect their copyright to religious works (this action was taken in the USA).