If you open the documentation and type a key to search with, it will show you all results. After you click in one of the results, the search text box is not cleared. If you select the text box again and hit Enter, it will not search for that key. To perform the same search you would need to delete the text, type it again and press Enter.
I would be happy if either, the text box clears itself once you click a result, or if bringing it back to focus and clicking enter will use the last value.