Can I file deceiving case and demand complete land from relatives

Respected sir, 10 years ago we purchased a land from our relative but that time we trust them and didn't do any legal document as a proof.except handwritten document subject is "we r doing transaction of land".now since last 3,4 years they are avoiding..somehow they agree to give us 2 acres out of 3 acre's transaction.and we did registered " Sathe khat".every document we did but still our name isn't on 7/12.so what can we do?i want your advice about this- sir,can I file deceiving case against them and demand complete land or money at market price?? How strong my case?? Plz sir guide me..