In the assets pane under the Blocks tab there's a search field, how is that supposed to work?
I've created several blocks but whatever I type in the search field the result is always "Content not found". I've tried to search for both block names and also content in blocks with no result.
What search provider are you running in the UI? Both EPIServer Find and the built in search "FTS" support searching in blocks. You enable them by going to admin -> config -> Search Configuration.