The options accessible from the 'Refine' button on a search result are customisable
In the administration interface, you can use filters to refine your results in all search modes:
These filters are dynamic and can be customised by the administrators to ensure that only relevant filters are displayed.
To set up the filters, go to the administration interface, in the 'Search' section of the 'Settings' tab. Simply add/remove the relevant fields in the 'Faceting' section.
Please note! The changes you make apply immediately to ALL users.