To configure a result source, follow these steps:

1. Locate the Manage Results Source page for the scope of the search:

• For the tenant, this is located on the Search Administration page (https://admin.microsoft.com | Admin centers | SharePoint | Classic Features | Search). In some tenants, however, the Manage Result Sources page is located at https://admin.microsoft.com | Admin centers | SharePoint | More Features | Search | Manage Result Sources.

You can also skip the navigation elements and go directly to https://<tenant>-admin.sharepoint.com/_layouts/15/searchadmin/ManageResultSources.aspx?level=tenant, where <tenant> is your tenant's default domain.

• For either a site collection or a site, navigate to the site, click the gear icon, select Site information, select Site Settings, and select View all site settings. Locate either Search Result Sources (site collection) or Result Sources (site).

2. Click New Result Source:

3. Fill out a name and description for the result source.
4. Select a protocol; most likely, you'll be configuring Local SharePoint (the default), but you do have other options. If you want to configure an on-premise SharePoint farm as a result source, you should configure SharePoint Hybrid (which is beyond the scope of the MS-300 exam). Finally, you can choose OpenSearch 1.0/1.1 to send queries to an external search service, such as Bing, that supports the OpenSearch protocol.
5. The default query transform is {searchTerms}, but you can use the query builder to create your own. If you launch the Query Builder tool, you can specify query filters on the BASICS tab, sort options on the SORTING tab, and then test out your query on the TEST tab.
6. Click Save.

After creating a custom result source, you may want to use some custom query rules that will use this result source.