how to use FindAFEventFrame.Query Property

I am struggling to understand how to use properly the query property with Find-AFEventFrame

 

I have been able to do this kind of basic EF searches

 

Find-AFEventFrame -StartTime (ConvertFrom-AFRelativeTime "y") -EndTime (ConvertFrom-AFRelativeTime "t") -AFDatabase $AF_DB -AFSearchMode Inclusive

 

 

but I really need to understand how to automatize some of the searches I am doing with PI system explorer

I guess I should use the -query property, unfortunately I was not able to find any example in the documentation on how to use it, practically