It gets more complicated without access to the document, however the following may work for you. It bookmarks from CEO: to the next full stop.
Code:
Sub Macro1()
Dim orng As Range
Dim i As Long
Set orng = ActiveDocument.Range
With orng.Find
i = 1
Do While .Execute(findText:="CEO:*.", MatchWildcards:=True)
orng.Bookmarks.Add "mark" & i
i = i + 1
orng.Collapse 0
Loop
End With
End Sub