MySQL fulltext searching considers a period a stopword character, so it is trying to search for 4 or 0 or 9, and since a word has to be 4 characters or more, that will never find anything. This is a limitation of MySQL fulltext search I'm afraid. I'll bring it up internally to see if there are any improvements we can make as we rework search in an upcoming release.
I can't reproduce. Please submit a ticket if you're experiencing issues. Note that there is a "sidebar" location at the footer of the page as well, which may be what is showing here (I can't tell for sure from the screenshot).