Once you've created and saved your search engine, you can easily go back to edit the settings. Simply follow the instructions below:
- Sign in to your AdSense account.
- Click Ads for Search.
- Find and click the name of your search engine in the list.
- After implementing changes, click Save and get code
Most changes will automatically be visible on your site wherever that search engine appears. There's no need to update your search code unless you've made changes to the look and feel of your search box, your site encoding or language preferences, or whether your results pages will be hosted on your own site or a Google-hosted page.