Property issue which is almost 20 years old

Respected sir, Your kind advice on my home matter(property issue) please read the matter as follows 1.my mother is a single daughter to my grandfather after marriage both grand mother and father died. After that all property of my grandfather was distributed by cousin brothers among themselves. 2. My grand mother & father died since more than 20 yrs passes. My mother not asked the property with cousin brothers. Even there death certificates not registered nor taken out. But the as per record of 7/12 papers whatever property is there my name is there on papers 3. This case has given to the advocate he is saying now after two years, the case is very complicated. 4. Earlier i asked to tahshildar office on this matter they said book a complaint against them who ur property taken and also written RTI on same matter for solution but reply not feasible. 5.One more thing that actual property with whom and how much i! don't no. 6. Request advise