Hi @Quang Hieu ,
Welcome to our forum!
When I search for emails, the new ones appear, but they don't show in the Inbox.
When you search in the Outlook, please check the location of the new email as shown in the below image.
If it is truly in Inbox folder, considering that it may be related to some View setting changes, it's suggested that you could try to reset view to check if new emails can be displayed successfully.
Hope to help you!
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