chain skills blue prints

[sandra1957]

If the title confusing you its when you combine skills like say tragedy(kana and kyouka combo after their special attack has been unlock you know that kinda like exe in neptunia) use this move and get the trophy called ultimate attack (theres a quest that you have to use this on ch. 4 or 5 its the one where about a concert) now onto my question:

 

Where and when can you get blue prints for the chain skills cause I only unlock a few but still need location for the rest of them for some trophies that hard to grab