I’m not sure what is being referred to in the answer supplied below. I need to clarify your question and hopefully point to a solution.
Contrary to your question: It is not possible to pull data from other views into a Notes view. A formula can only pull in documents based on the selection criteria.
Contrary to the answer below: It is not possible to write a selection criteria to pull a document into a view twice. The formula defines the criteria for what documents should appear in the view. If a document meets more than one criteria for inclusion, it can only appear in the view once.
Therefore, I suspect you have duplicate data. Right click one of the documents and display its document properties. Check the create and modified dates. Write down this information. Leave the properties box open. Click on the other document in the view. you will see that it has different create and modified dates. Delete the duplicate, being sure to keep the one that has relationships with other documents, if any. Update the surviving document with information that makes it current, if the document you need to delete has more up-to-date stuff.
CAVEAT: You can see the same document twice in a view if you are categorizing on a field that contains multiple values. You will see the same document under each separate value in the categorized view. This is normal and expected.
Hope this helps.
I’d double check the formula you have in the field that is giving you duplicates via designer and ensure you didnt specify an entry twice by accident in your formula. Also verify your view selection for the view as a whole is correct.