You need to set up your permalink structure for wordpress to recognize the “/פרסונות” url as the default search page. Currently your main url works, for example: http://www.persona.org.il/?s=test
The plugin is working correctly, it redirects to the correct page, but wordpress doesn't know that it should be the search page.
I think you need some kind of modification to your .htaccess file, but I'm not sure.
I've found a tutorial that might be helpful: http://wpengineer.com/2258/change-the-search-url-of-wordpress/Best,
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