Create different format on Advanced Search widget.

Hello, I am currently using a Wordpress theme, which is for a directory theme. There are multi-select options on the submit page (when members submit an event or listing). The problem is, on the search widget on the site, the multi-select options are not in a drop-down' format. They are taking up too much space. I would like this option to be turned to a drop-down list. There are also 2 sites with the same issue. Thanks