[Brian]

The usual suspects here are the search tool filtering everything out of view because something that doesn't match any of your actions was entered, the contents of the window being scrolled up out of view (that one's a bug), or some funky View menu settings causing nothing to be shown.

If hitting All Items doesn't show your actions, please attach your OmniFocus database to an email to the support ninjas - Send Feedback under the Help menu. We can usually un-tangle whatever happened. Your database is stored in
<your home folder>/Library/Application Support/OmniFocus