When searching for users with their full name (Steve Swinsburg) you will find 0 results, even if that user exists. The issue is that the search takes the entire term and applies it to the first and last name fields, but since neither field matches exactly, then it fails.
To verify, as an admin go to the Admin Workspace and click 'Users'.
1. Search for 'Sakai'. You should get at least the Sakai Administrator user.
2. Search for 'Administrator'. You should get at least the Sakai Administrator user.
3. Search for 'Sakai Administrator'. You will get no results.
A possible fix could be splitting the search terms on whitespace and then performing multiple searches on all fields with both terms and then combining the results. Although I am not sure how this would fair with people that have spaces in their last name ie 'De Paul', it would probably give some odd results (finding people with De in their first name).
Maybe a smarter search with search operators? Although that is more complex.