Navigate to SharePoint admin center using the below linkhttps://tenant.admin.sharepoint.com/_layouts/15/online/AdminHome.aspx
Go to SharePoint Admin > User Profiles > Manage User Properties.
Click on New Property to create a new property.
- Go to SharePoint >Admin > User Profiles. Click on the Open button. Now click on the Manage User Profiles.
- Update profile for one user.
- Go to SharePoint Admin > Search > Manage search schema > Crawled Properties.
Please wait until the new property shows up. This may take a little while (anything from 15 mins to 4 hours).
The type of information in this property:Text. Select the check box Searchable, Queryable, Retrievable .
Click Advanced Searchable Settings and select PeopleIdx in the popup window.
Click the blue button Add a Mapping.