Three Moves Ahead

I struggle to find moves like 7.... d5. Because the logic, or the consequence, is not right in front of eyes. Like I need to move 7.... d5 because that d4 pawn is  blocking bishop from coming to protect knight, that is , blocking potential Be7. But well , d5 is not an obvious move because it has exd5 coming. Now , I am seeing exd5, so I did not move d5. I am unable to calculate two moves to see potential Be7 blocked. And may be a little blame can be put on that Queen that created an illusion that my knight is protected (Well it is, until Bg5, which , is a common move, but definitely I couldn't understand I would need Be7 and that have been blocked., and I need to sacrifice a pawn to unblock the bishop.). What can I do about this? I believe one of the reasons  of my low rating is not understanding these three move threats. 

(Please don't come up with my recent outright blunders in other games anyone, those are not the whole story.)