Search in multidimensional object

I try to search on a simple multidimensional object. But nothing return result.

var sifter = new Sifter([
{
  lastName: "John",
  firstName: "Doe",
  email: "jdoer@anonymo.us",
  society: {
    id: 1,
    name: "ONU"
  }
}
]);

I have try:

var result = sifter.search('onu', {
    fields: ['lastName', 'firstName', 'society.name'],
});

var result = sifter.search('onu', {
    fields: ['lastName', 'firstName', 'society[name]'],
});

Thank you for your reply.

brianreavis / sifter.js

Search in multidimensional object #48