We Didn't Know This Until Now

A Brief Introduction About Our Property. It Is An Ancestral Property From My Mother's Side. My Maternal Great Grandmother Has Split The Property (Document A) Between My Grandfathers. There Were 4 Grandfathers In Which My Mother's Father Is The Third Son. Among These Four Grandfathers, 2 Of Them Knew About This Property But Not The Other 2 Which Includes My Grandfather. So Only Recently We Came Across The Above Said Document A. According To That Document We Have Around 6 Acres In Five Survey Numbers. As We Were Researching About This Property, We Came To Know Something. Within Those Five Survey Numbers, People Have Forged Fake Documents And Sold Our Land In 2 Survey Numbers. And These Fake Documents Date Back To 1962. I Have A Lot Of Questions, But Let Me Start With This One. Will We Be Able To Get Our Land. If So, What Are The Procedures? Thanks In Advance.