Dim lPos As Integer
    Dim sText As String
 
    lPos = -1
    sText = "hallo"
    With RichTextBox1
      Do
        lPos = .Find(sText, lPos + 1, RichTextBoxFinds.None)
        If lPos >= 0 Then
          .Select(lPos, Len(sText))
          .SelectionColor = Color.Blue
        End If
      Loop Until lPos < 0
    End With