How to locate ancestral land

In 1968 my grand father purchased 3 acres of land out of 4.04 acre Khasra located at Nagpur. He formed a layout of 38 plots & sold them, after selling those plots, a piece of 24000 sq foot was left by him for his future. in the latest 7/12 its area is mentioned as 0.23 hectare. After the demise of grandfather ,randomly we saw that 7/12 & sale deed of 3 acres. We had been to that khasra to identify the leftover land but we are unable to locate our part of land. The talathi of that area is newly posted & hardly answers any of the questions of mine. This property is located in a good area, such a big piece of land is not visible anywhere, some slum houses are seen scattered at different different places. I want to identify my remaining part of land, & its four corners. I also have received the layout map via RTI from Nagpur Improvement trust of the layout which was formed by my grandfather. I also have village map(revenue) but the village map only shows the boundaries of the Khasra & not its various divisions. Awaiting for your suggestions & remedies! Thanks in advance & regards.