If you are seeing a specific number like "(68)" in your search header, it indicates that Outlook has found that many matches in your local index or initial server query . Why Results Are Limited
If your search results are consistently lower than expected or missing files, it may be due to: Troubleshooting Outlook search issues - Microsoft Support
If the 68 results shown are not what you need, you can expand the search: Search results for office 2016 (68)
Users can permanently increase or remove this limit by adding a registry key. Navigating to HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Search and creating a DWORD named SearchResultsCap with a value of 0 will show unlimited results . Common Search Issues in Office 2016
Microsoft introduced these caps to prevent long wait times while searching large mailboxes. If you are seeing a specific number like
This "cap" allows for "lickety split" response times .
In Outlook 2016 and later, the application first submits a query to the Exchange server before rendering results . How to View More Results Common Search Issues in Office 2016 Microsoft introduced
Most users see a maximum of 250 items initially .