Sub FindInsideParanthesis()
Dim StrOut As String
With ActiveDocument
  With .Range
    With .Find
      .Text = "\(*\)"
      .MatchWildcards = True
      .Execute
    End With
    Do While .Find.Found = True
      'The next two lines exclude the start/end characters from what gets processed
      .Start = .Start + 1
      .End = .End - 1
      StrOut = StrOut & vbCr & .Text
      .Collapse wdCollapseEnd
      .Find.Execute
    Loop
  End With
  .Range.InsertAfter StrOut
End With
End Sub