I had given approx 100 RCs from DT still did not get any significant improvement. What should i di??should change my strategy or practice a lot more??

Instead of solving RCs like LRDI or Quant, try reading for reading's sake. Understand what the author is trying to convey. Solving techniques comes later, you should read long complex essays in websites like Aeon Essays or Editorials from reputed publications. You'll see a huge jump in your scores once you begin to register the information given in the passage in your mind.

Also, try lowering your reading speed. It helped me improve my accuracy by a lot when I started.

thank you