What is the correct filter string to display a name from source file of Asset Metadata?

Does anyone know the correct Filter String for Source File from Asset Metadata?

I want to create a custom filter and write a name on the source file to filter my assets on the content browser. I thought would be like SourceFile=ENV for example but it’s not working.

For Path=ENV for example works well, however it searches the path on content browser. What I need is the File Path of Source File.

It’s not case-sensitive and can’t have space in between words.
Does anyone know the correct syntax?