Based on what you have shown and described:
Code:
Sub ScratchMacro()
'A basic Word macro coded by Greg Maxey
Dim varFactors
Dim lngIndex As Long
Dim strFind As String
Dim oRng As Range
Dim strDesc As String
varFactors = Split(Selection.Text, ",")
strDesc = InputBox("Enter a decriptor")
For lngIndex = 0 To UBound(varFactors)
Set oRng = ActiveDocument.Range
With oRng.Find
.Text = Trim(varFactors(lngIndex))
.MatchCase = True
While .Execute
If oRng.InRange(Selection.Range) Then
'If you need to expand the range of the defined text do it here before applying the BM
oRng.Bookmarks.Add strDesc & lngIndex + 1, oRng
End If
oRng.Collapse wdCollapseEnd
Wend
End With
Next
lbl_Exit:
Exit Sub
End Sub