In these first days of 2022 you may have problems in the search function of your Outlook. For example, you might want to search for emails from a certain contact and only get emails received before 2022.
The problem is caused by a Windows update affecting the Windows search function. The update is KB5008212. Then check for Windows updates to see if you have this update installed.
How to solve?
To date (12th January 2022) Microsoft has not yet released an update that fixes the problem.
If you’re in serious trouble and don’t want to wait, Microsoft has released a workaround that disables the “Windows Desktop Search” which is the source of the problem for Outlook. It is an operation to be performed on the registry. At this link you will find the official Microsoft statement and the instructions for the workaround: Outlook Search not showing recent emails after Windows update KB5008212