Have you noticed different results when searching in Mobile outlook app. It seems to back a week for some and years for some messages. is it returning just number of messages. One thing that is common with the Outlook mobile app is that is not producing consistent results.
Like in the native mail there is no option to define a time period for the mail like the below screenshot
It seems like either it goes back for a week or returns like 10 messages at a time in the search. Uninstalling outlook and reinstalling does not fix the search issue and Microsoft have not confirm how many messages should the search return.
Per MS support it works as designed that the search results are different between Outlook Mobile app and Desktop Outlook as they have different mechanism for searching
Below is the Roadmap link to track the features listed in Roadmap:
https://www.microsoft.com/en-us/microsoft-365/roadmap?ms.url=roadmap&rtc=1&filters=Android%2CiOS
Thanks
