@topo morto gave a great technical explanation.
I would like to add:
I highly recommend that you go visit your nearest guitar store and try a variety of guitars. You might find that either your strings are old, guitar body is damaged, your neck needs a setup, or you simply don't like the way classical guitar sounds. You'll find out by trying out what
resonates more for you.
My very first guitar was a $12 classical guitar from a yard sale that I received as a gift. I do remember asking myself why the guitar wasn't resonant enough, but I think that was because I was influenced by electric guitars and acoustic guitars on youtube and on albums, I expected the same sound on this guitar. Nowadays, I go back to this guitar appreciating the way it sounds.
Also remember that a lot of guitars you hear in the media are mic'd, so they will sound different than how you hear it against your body.
I hope that helps!