The only thing you can do really is to set up the reference field display value so that it contains information that makes sense to everyone. Typically I handle this type of thing by creating a new field and then calculating the value in it. You can see a good example of a calculated field by looking at the dictionary entry for the 'Name' field on the 'sys_user' table. 'Name' is actually a calculation of First and Last name. You could then set up this new field to be the display field for its table.

When you do something like this, it often makes sense to change the autocomplete search behavior for that table to use a 'contains' search instead of a 'starts with' search.
http://wiki.service-now.com/index.php?title=Customizing_Autocomplete_Search_Behavior

Also, calculated fields will display a calculated value immediately for all of the records in the table, but the calculated value is not actually stored until each record has been updated. This means that if you want to be able to search on the new calculated value you need to update all of the records in the table that the calculation exists on.