Duane Hookom's - Concatenate and filter by Column

[BBBryan]

Hi,
I was looking for help.
I am using Duane Hookom's Concatenate Module.
I am using this in my query
CombinedRRs: Concatenate("SELECT DISTINCT [No] FROM [RR tbl] WHERE RR =""" & [RR tbl].[RR] & """")
this works good But I want to filter by another Column [CompleteDate]
If the [CompleteDate] Not Is Null. I only want those to Concatenate.

I am not sure how to write this.
Thanks BBryan