Sub FindAndReplaceMultiItems()
  Dim strFindText As String
  Dim strReplaceText As String
  Dim nSplitItem As Long
   
  Application.ScreenUpdating = False

  strFindText = "northenn,westenn"
  strReplaceText = "northern,western"
  
  nSplitItem = UBound(Split(strFindText, ","))

  ' Find each item and replace it with new one respectively.
  For nSplitItem = 0 To nSplitItem
    With Selection
      .HomeKey Unit:=wdStory
      With Selection.Find
        .ClearFormatting
        .Replacement.ClearFormatting
        .Text = Split(strFindText, ",")(nSplitItem)
        .Replacement.Text = Split(strReplaceText, ",")(nSplitItem)
        .Format = False
        .MatchWholeWord = False
      End With
    Selection.Find.Execute Replace:=wdReplaceAll
  End With
Next nSplitItem

  Application.ScreenUpdating = True

MsgBox "DONE EXECUTION"
End Sub