Outlook Mobile Limited Search Functionality

Our users have recently started complaining that in using the search functionality in Outlook Mobile, they are unable to get results that they would on the desktop app when it comes to contacts. Specifically if they are searching for a contact whose details would be in the company field, or the details fields, they get zero results in Outlook Mobile. It seems to only be searching the display name. 

I'm not entirely sure if this just started happening, or has always been a thing, but we're getting reports. It seems odd that the experience for search wouldn't work the same. Is there something we need to do on our end, or is this a limitation / issue with Outlook mobile?