The file overview allows you to find and open files. The Filter and Type menus can be used to pre-fill the query input field. The input field itself uses the following syntax:

type:pl | swinb | lnk
Restrict the search to documents of the indicated type.
Restrict the search to documents attributed to a user matching Pattern. The Pattern me restricts the search to your documents. If you are logged in, these are documents created when you were logged in. Otherwise ownership is heuristically determined based on the avatar and nickname
Restrict the search to files whose name match Pattern
Restrict the search to files with a tag matching Pattern
Search for files containing String. Match is case insensitive.
Search for files whose content matches Regex. Flags is a sequence of the following flags: i (ignore case), x (Perl extended regular expressions), m (multiple lines) s (Perl dotall mode).
Search for files containing Word. Match is case insensitive.

The type:, user:, name: and tag: syntax may be followed by a sequence of non-blanks, a double quoted string or a regular expression written as /Regex/flags.

Search is executed after 2 seconds after a modification of the search field, on hitting RET or clicking the search button.