Have you looked at MergeMultiplePDFs Java action in community commons? Using this Java action, you can combine multiple FileDocs into a single FileDoc. One note: the max number of files you can merge is recommended to be no larger than 10, so if you’ll be combining more than that, you’ll need to build your microflow to do some intermediate merges to stay within that limit.
Hope that helps,
That helped me to handle this.
I just in dynamic loop created multiple single documents and then combined all to one new document which I send to download.
Thanks for the help.