combine more columns into 1 slicers

[Palacasi]

Hi,
I am trying to sort a table for documents correlated to a change using pivot table and slicers.
One change can be linked to many documents. One document can be linked to many changes.
What is the smartest way to create a table by change, and sort for document type?

• change 1
  • document A
  • document B
  • document C

• change 2
  • document A
  • document C
  • document D
  • document E

if i list the documents impacted by each change in one column, the pivot table will report the change only on the document of the first raw.
if i list the documents impacted by each change on the same raw, i have now different columns that need to be merged into one global slicer. how can I do that??
thank you!
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