Hi, Please check out these links on this issue.
http://stackoverflow.com/questions/3558228/crystal-report-combining-rows-of-data-into-a-single-value
Creating A Single String From Multiple Records | SCN
http://stackoverflow.com/questions/7154873/concatenate-a-single-database-fields-multiple-values
Concatenate field details into single field | The ASP.NET Forums
Regards
Saad