I think there is no direct way to achieve that, but you can use “edited:1” to search for notes added/modified today, which should include the cards you suspended.
UPDATE: After referring to Anki’s code, I’m not entirely sure this will actually work.
It seems suspending cards changes the card modification time, while the “edited” search only checks the note modification time, as the manual implies.
@dae, if I’ve not missed something, what do you think about introducing a search term that corresponds to the Card Modified browser column?