Needing Search trought everything.

Hi there, We need a search function throught the whole website. The website uses Clean-Journal-Pro theme combined with these plugins: BBPress WP-File Download The Events Calendar It's important to search throught members, files, events in the calendar and the articles. Could anyone help ? Is there a function with the theme to customize the search function ? Or do i need to customize the search function with an child-theme? If that would be the case does anyone know how i could do this ? I’d appreciate any suggestions. SOBildung Team