The issue occurs because Searchanise uses the template from the theme to show search results. Sometimes, this template could be too narrow.

You can resolve it by doing the following:

Change Custom CSS in the Searchanise admin panel by yourself. To do so, go to Searchanise app panel → Search Results Page → Custom CSS and make the necessary changes. New styles will be applied automatically once you save the settings.

Here is an example of the Custom CSS:

#search-results .container--tiny {
    max-width: 1600px;
}

Please note, this is not a universal solution and additional adjustments might be needed in some cases, please contact us at feedback@searchanise.com in case you need help. We will be happy to assist.