Moved this to Community Interface Help and inserted the image in the post as the board doesn't like external image links.
I think you need to be logged in, in order to perform a search.
If I go into the Business ePO sub-community I can search, using the search box at top right, whether I'm logged in or not, and up comes a page of results. Does that work for you too?
Was the search being done using some other method?