Yes, I am able to recover my files. I haven't checked yet whether all are recovered or not but yes a few I have checked are recovered. As there are many many files which are recovered via that tool/command I need to grep some text pattern in those files and see which are mine. The files are recovered with different names (may be generated by system). I got the solution from a different forum and the command is photorec
sudo photorec This will open a text based window. I followed the instructions and yes it's superb.
EDIT
Well though my purpose is solved but 1 thing that I found, I would like to say so that one can put some light on that. Please see, many files which I deleted were all recovered. But one thing: for 1 file I saw that the last saved matter wasn't recovered. I explain what I mean: I wrote a file, saved then edited again saved and edited.... For that file I see that many files are present in the recovered files. In 1 recovered file 5 lines of code (for that file) is present and in other 30 lines. But the matter that was present in the file when I last saved it couldn't be recovered. So what I mean is that intermediate matters are recovered of that file but the last saved one wasn't present in the recovered files. Does one has any idea why so!! Because it seems if previous matters are recovered then last saved should be obviously be present in the recovered files.