https://www.drupal.org/project/search404
The module performs a search using the keywords in the missing URL to select appropriate content to show to the lost visitor. For example, if a visitor goes to http://yourDrupal8site.dev/animals/cute- cats (which I assume doesn’t exist on your website) and finds nothing then this module will search for “animals cute cats” and display those search results below the “404 Page Not Found” error. This tweak to the 404 page helps your SEO by making sure that old or badly written links to your site will still resolve. It helps visitors find your content. You want visitors to find great content on your site. You especially want Google to be able to find related content if the indexed page has been removed.
Install and Enable the Search 404 Module
- Install the Search 404 module on your server.
- Go to the Extend page: Click Manage > Extend (Coffee: “extend”) or visit http://yourDrupal8site.dev/admin/modules in your browser.
- Select the checkbox next to “Search 404” and click the Install button at the bottom of the page. There are no separate permissions required for the Search 404 module.
Configure the Search 404 module
- Go to the Search 404 module admin page by clicking Manage > Configuration > Search and metadata > Search 404 Settings (Coffee: “search404”) or visit http://yourDrupal8site.dev/admin/config/search/search404 in your browser.
- Configure the module as shown above: A. Select the checkbox “Jump directly to the search result when there is only one result”. B. Select the checkbox “Use a 301 Redirect instead of 302 Redirect”. C. Select the checkbox “Use auto-detection of keywords from search engine referer”. D. Although there are many options on this page, you can leave most of them as you find them.
- Click the Save configuration button.
