Finding someone address

Against whom (unknown), where (address) you have stated to have filed suit ? Has the suit been admitted without name and address of defendant ?

Prima facie fabricated facts.

I know his name and address. He was a tenant in that address before. After that he left that place and no one knows where he moved. Not sure his previous address would be suitable to continue the case. 

As you had taken steps to serve the summons to his last known address whereas he is not found in that address, then you may have to take the summons through substituted service by publishing the summons through newspaper with the permission of court.

You discuss with your lawyer on such routine issues.

Seek permission and get substituted service by way of publication, if you fail to service notice/ summons on the last known address.

It would be better to consult your lawyer and/or some other local  prudent lawyer for proper analyses of facts, professional advise and necessary proceeding.

Yes, take steps for substituted service.