Thank you so much for your advices!
Mix media is a big and wonderful world! Jejeje.
Here is a playlist of videos I made, playing with different mediums.
https://www.youtube.com/playlist?list=PLtDPQ-VhZhQsnI6a7-XxkMozoDipQeD1g
Did you try to use clear airbrush? It will secure your painting and make the paper a little bit stiff.