How it works today
The fulltext search of content from the input box works. Using the Custom Query for more advanced searching also works.
The input search works as a “contains” and an “or” type search of content today, so if you search cats dogs, you see content with cats and content with dogs. You can add double quotes to search for an exact phrase, so "cats and dogs" with double quotes will find only content containing that exact phrase.
What could be improved
The input box search could be improved by adding search tokens to represent the commands available in the Custom Query popup. For example, ^test could search for all content that starts with test. And $test could search for all content that ends with test. And so on.
Something like this may be built in to the fulltext search tool, but it’s not clear because it’s not documented in the UI and I couldn’t find it in the forums. So if there are existing search options already, showing a cheat-sheet/help popup near the input box would be a big help.