With regard to the search issue, please make sure that there isn't any Outlook Profile Folder (Main Profile folder) added in Privacy window because, if Outlook Profile is added in the Privacy window then, search will not work.
If there isn't any folder added in the Privacy window then, let’s re-index the hard drive and see if that makes any change to Outlook.
Please follow the steps listed below to do so: 1. Open System Preferences and select the Spotlight. 2. Click the Privacy tab. 3. Click Finder and then under Locations click your computer name 4. Drag the Macintosh HD to the Privacy tab and wait for some time (5-10 mins). 5. From the Privacy window, select the HD and then click the minus (-) button near the bottom left of the window.