[BitBucket user: Francisco Venancio]
[BitBucket date: 2016-07-11.14:42:39]

Yes, I'm aware of the manufacturer fourth parameter.
Perhaps I was not clear. The issue is about the response to calls to /modalites/{modality}/query . In Orthanc Explorer the queries are sent with asterisks, we had to change it to empty strings so that the queries came back with any answer, namely we changed :
'Query' : {
      'AccessionNumber' : '*',
      'PatientBirthDate' : '*',
      'PatientID' : '*',
      'PatientName' : '*',
      'PatientSex' : '*',
      'SpecificCharacterSet' : 'ISO_IR 192',  // UTF-8
      'StudyDate' : $('#qr-date').val(),
      'StudyDescription' : '*'
    }

to 
'Query' : {
      'AccessionNumber' : '',
      'PatientBirthDate' : '',
      'PatientID' : '',
      'PatientName' : '',
      'PatientSex' : '',
      'SpecificCharacterSet' : 'ISO_IR 192',  // UTF-8
      'StudyDate' : $('#qr-date').val(),
      'StudyDescription' : ''
    }

in query-retrieve.js.