title: laravel query for delete where date < now() with INTERVAL N days
body: <p>I am working on a laravel project now I stuck on a query. I want to use this query: </p>
  
  <pre><code>DELETE FROM on_search WHERE search_date &lt; NOW() - INTERVAL N DAY
  </code></pre>
  
  <p>but cant converted into laravel like DB::table('table_name)->where(......)-> _____ ;</p>