Will find all Content Items which have the Layer "Corporate Information" assigned, but there is no English value for the Title available aka this syntax finds all Content Items with an empty Title in the Layer. 

-_exists_:fieldpath AND layerSchemaIds:LayerId

corporateInformation.title.en is the fieldpath to the English value of the translated text on the layer Corporate Information. 

The special field: layerSchemaIds has the Layer names stored as a value for easy access. 

For text fields without translations remove the language abbreviation: corporateInformation.title.

-_exists_:fieldpath AND layerSchemaIds:LayerId

-_exists_:corporateInformation.title.en AND layerSchemaIds:CorporateInformation