Hi Ckumari,
Please take care, most of surveys use the schema nms:webAppLogRcpData (so the same for you with Data extension for your custom target mapping).
The webAppLogRcpData contains values responses as archived fields in XML format (memo fields, cblob/TEXT sql column).
In order to have Response tab filled, please check in your webApp, in Properties page, select Advanced parameters and look for the checkbox Save the response trace (I don't remember exactly the label corresponding to the French label below):

Some of the Response list are filled with webAppLogRcp schema content, other with webAppLogRcpData content.
Regards
J-Serge