Rewind particlesystem. Play it backward

Hi guys I want make somthing like inhale effect after blow. In first few second particle system will play normlany but after this few second particle will play rewinded but how to make particle rewinded? I can't find any information about that

 czas = czas + time.deltatime
 
 if (czas <=4) // patrilce system playing forward
 {
 particle.enableEmission = true;
 }
 if (czas > 4  && czas <=8) // particle system playing backward form position where  "czas" get value >4 
 }
 //here we make rewinde particle system 
 }
 if (czas > 8 ) // RESET to play it again in next frame 
 }
 czas = 0  ;
 particle.enableEmission = false;
 }

Any sugestion ?