var Person = mongoose.model('Person', yourSchema);
   // find each person with a name contains 'Ghost'
   Person.findOne({ "name" : { $regex: /Ghost/, $options: 'i' } },
          function (err, person) {
                 if (err) return handleError(err);
                 console.log('%s %s is a %s.', person.name.first, person.name.last, person.occupation);

   });