My ex-wife denied visitation rights to me and my parents

Me and my wife were divorced mutual concern during 2013 in India, my son was 4 years old that time. In the mutual concern agreement, it stated, she is the custodial parent, also my child care, maintenance responsibilities taken care by my ex-wife and In the agreement, there is nothing mentioned about visitation rights to non-custodial parent (me). After 2 years of divorce, I contact her through electronic means (email/phone) and requested to show my child (at least photo of my son), she block / deny me in all possible ways. For example, she destroys all the traces related to me, using her name as First name for my son etc. I am not sure whether my son remember my face, last seen him during 2013 and its almost 8 years. During 2017, I just came to know through linked-in that she moved to US with my son without prior intimation to me. Though she moved, I tried sending emails to her work mail id asked about my son, requested to come through video call. Again recently, I came to know that she shifted another job over there in US few months back. I was not able to trace her address. I tried to contact her parents but they are also out of state (not able to trace address). I want to see my son but she deny visitation rights to me, I was suffering a lot due to this issue since many years but she don't even consider me. Kindly advice me how to solve this issue. I am basically from a middle class background, not rich. I am working for a private concern. I am searching my son since many years awaiting to see him.