what the name of this vastly used technique in guitar rhythm sections (specially done with flamenco or classic guitars) and has a chick chick sound? I know how it is played but I don't know the name. May someone help me? Sorry if I have not asked this question in a right place!
That is called dead notes or muted notes in acoustic finger style and classical. I am not sure what exactly is is called in flamenco.
Since I don't know which of the sounds you're talking about, it's either 1) just the clicking of the player's nails against the strings being picked up by the mike, or 2) the rasgueado technique, basically hitting stings 4->1 with 3 or 4 fingers in any number of strokes.