Você provavelmente precisa definir a propriedade .Wrap
de .Find
...
Selection.Find.Style = ActiveDocument.Styles("Heading 2")
Selection.Find.Wrap = wdFindStop
...
Find.Wrap Property:
Returns or sets what happens if the search begins at a point other than the beginning of the document and the end of the document is reached (or vice versa if Forward is set to False) or if the search text isn't found in the specified selection or range. Read/write WdFindWrap.
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