How to get the material on record which IO intentionally suppressed ?

Hello, A friend of mine is facing a false case under sections 376, 354D, 506 and 448. Police had filed chargesheet, The allegation is from year 2015 to 2017 in her complaint. It is mentioned in complainant's 161 statement that accused used to call from his number xxxxxxxxx to her number yyyyyyyyyy and demand to full fill his sexual desires if not he would tarnish her image in the society. The call duration between both numbers mentioned in her statement is around 400 hours. Police had intenitionally not included the call details in the chargesheet So the question is .. how do we get that call details on record before the case is commited to the sessions court ?