In case you are not making much headway even after repeated attempts, make sure to check out the following
- Make sure that you are using the zipcode that corresponds to the latest address. Searching a person who might have relocated to another address is futile.
- You will get only an abbreviated version of the roll for online search . Probably the person you are looking for might have opted out of the list.
- Electoral rolls list out people according to the constituencies. Check the boundary commission report to make sure that the constituency has not changed over the years.
- Having checked all the essentials, you have a fair chance of finding someone with whom you have long lost contact.