You can add an extra field to the report's cursor that identifies detail records. It could be "1" for detail1, "2" for detail2 and "3" for detail3. Create one report group on the new field + group existing expression. Use 'Print When' in the page header/footer to print appropriate fields for each detail record.

>how can i print report with condition:
>can display information from 3 tables with 3 group expressions but how to display 3 detail row, i have had try, but always only can display 1 detail row.
>
>example:
>page header
>group header 1
>group header 2
>group header 3
>detail
>group footer 3
>group footer 2
>group footer 1
>page footer
>
>how can i change into:
>page header
>group header 1
>detail 1
>group footer 1
>group header 2
>detail 2
>group footer 2
>group header 3
>detail 3
>group footer 3
>
>or anyone can help me with another trick to display the same informatin with my beloved condition above :)
>
>thanks a lot before & after