One of the Web Security Services (WSS) features is Safe Search, a mode that provides the settings to allow or disallow displaying links to mature or inappropriate sites and image results when using the browser's search function without the need of creating any policy on the WSS portal.
To see the status of the Safe Search in WSS go to Solutions > Content Filtering > Search Controls.
The options to set this functionality are enable and disable.
This will set for Google engine and for all other search engines, by default the setting is enabled. After you change the setting, click on Activate.