Hi,
FYI: The USS languages can be found and modified in the "webapps\front-office-hook\WEB-INF\classes\content\"f under the tomcat folder.
you will need to modify the Languages-ext.properties file and the others corresponding to the language you support.
In your case the language you are looking for come from the Service Catalog widget and the languages will need to be modified there.
hope this help.
\J