Can Unicom employees read the content of users' mobile phone messages casually?

The content of users' short messages is personal privacy, which all employees of Unicom can't see. Unicom only provides detailed list query of mobile phone users in the past six months (including the current month), including call, SMS/MMS, value-added, data details and so on. The short message list can only view the receiving time and quantity of short messages, but not the content of short messages.