Hi Krunoslav! An important thing to recognize is that there are actually TWO blues scales. One is the "minor blues scale", which is basically the minor pentatonic you mentioned with an extra note (the b5) added. And the other is the "major blues scale", which is basically the major pentatonic with an extra note (the b3) added. In the key of C for example... Minor blues scale: C Eb F Gb G Bb Major blues scale: C D Eb E G A I do not have any sort of formal training in musical theory of deep understanding of classical western harmony, but learning/practicing how to move between these two scales while improvising really opened up country guitar playing for me.