Export WSB-logs using PowerShell

Hello,

i am trying to find a solution to export the Windows Server 2008r2/2012 Windows-Server-Backup logs WITH content of the message to a .txt

I have found this :

Get-WinEvent -logname "Microsoft-Windows-Backup" | where {$_.timecreated -ge $yesterday} | Format-Table TimeCreated, ID, ProviderName, Message -AutoSize -Wrap

But this is not exporting the messages like "backup cancelled", "backup started" , "backup completed".

Anybody with an option for this?

Thx