Python elasticsearch-dsl query nested field

Python 3.x Elasticsearch:

1. elasticsearch==6.1.1
2. elasticsearch-dsl==6.1.0

Elasticsearch model:

class VendCompanyData(DocType):
    data = Nested(
        properties={
            "machine_id": Integer(required=True),
            "product_id": Integer(required=True),
            "quantity": Integer(),
            "insert_time": Date()
        }
    )
    last_export = Date()
    created_at = Date()

    def save(self, **kwargs):
        self.created_at = datetime.now().strftime('%Y-%m-%dT%H:%M:%S.%fZ')
        return super().save(**kwargs)

Some data for nested filed:

[
            {
              "machine_id" : 1229,
              "product_id" : 3323,
              "quantity" : 1,
              "insert_time" : "2017-03-13T12:48:10.156026"
            },
            {
              "machine_id" : 1593,
              "product_id" : 3998,
              "quantity" : 1,
              "insert_time" : "2017-03-13T12:48:23.296982"
            },
            {
              "machine_id" : 1485,
              "product_id" : 3979,
              "quantity" : 1,
              "insert_time" : "2017-03-13T12:48:44.989393"
            },
            {
              "machine_id" : 1476,
              "product_id" : 8212,
              "quantity" : 1,
              "insert_time" : "2017-03-13T12:48:54.282708"
            }]

And now elasticsearch-dsl query for query only machine_id, and logic returns only that machine/s from the array.

Query:

get_last_machine= (
            Search(using=cls.client, index=cls.vend_index_today)
            .filter("nested", path="data", query=Q("term",  data__machine_id=machine_id))
            .source(['data.machine_id'])
        )

What query returns is all data, not only one what I've asking in the query.