Issue with Aggregating Nested Documents in Elasticsearch

I have this json document:

{"docs":[{"id":"1","abono":10000,"cargo":0,"descripcion":"Abono"},{"id":"2","abono":0,"cargo":23000,"descripcion":"Pago Remuneraciones","Remuneracions":[{"id":1001,"empleado_id":111,"monto_liquido":12000,"CartolaDocumento":{"cartola_id":555555,"monto_convertido":12000},"Prorratas":[{"cuenta_id":333333,"monto":12000	}],"Empleado":{"id":111,"nombre":"Alvaro"}},{"id":1002,"empleado_id":222,"monto_liquido":11000,"CartolaDocumento":{"cartola_id":555555,"monto_convertido":11000},"Prorratas":[{"cuenta_id":333333,"monto":11000}],"Empleado":{"id":222,"nombre":"Santiago"}}]}]}

I send this json document to Elasticsearch with logstash with this configuration:

input
{
file { path => "/tmp/doc.json" start_position => "beginning" ignore_older => 15552000 codec => "json" add_field => { "producto" => "lalala" } }
}
filter
{
        if [producto] == "lalala"
        {
                split { field => "docs" }
                mutate { remove_field => ["host", "event", "log"] }
        }
}
output
{
        if [producto] == "lalala"
        {
								elasticsearch { index => "%{producto}" hosts => ["https://1.1.1.1:9200"] user => "shipper" password => "${shipper}" ssl_enabled => true ssl_certificate_authorities => "/etc/certs/ca/ca_twd.crt" action => "update" doc_as_upsert => true retry_on_conflict => "10" document_id => "%{[docs][id]}" }
				}
}

That creates two documents in Elasticsearch. I want to create a visualization that affects the second document. This is the document:

{
  "_index": "lalala",
  "_id": "2",
  "_version": 1,
  "_score": 0,
  "_source": {
...
,
    "docs": {
      "id": "2",
      "abono": 0,
      "descripcion": "Pago Remuneraciones",
      "Remuneracions": [
        {
          "monto_liquido": 12000,
          "Empleado": {
            "id": 111,
            "nombre": "Alvaro"
          },
          "CartolaDocumento": {
            "monto_convertido": 12000,
            "cartola_id": 555555
          },
          "id": 1001,
          "empleado_id": 111,
          "Prorratas": [
            {
              "cuenta_id": 333333,
              "monto": 12000
            }
          ]
        },
        {
          "monto_liquido": 11000,
          "Empleado": {
            "id": 222,
            "nombre": "Santiago"
          },
          "CartolaDocumento": {
            "monto_convertido": 11000,
            "cartola_id": 555555
          },
          "id": 1002,
          "empleado_id": 222,
          "Prorratas": [
            {
              "cuenta_id": 333333,
              "monto": 11000
            }
          ]
        }
      ],
      "cargo": 23000
    }
  },
  "fields": {
    "docs.Remuneracions.Prorratas.monto": [
      12000,
      11000
    ],
    "docs.descripcion": [
      "Pago Remuneraciones"
    ],
    "producto.keyword": [
      "chipax"
    ],
    "docs.Remuneracions.Empleado.nombre": [
      "Alvaro",
      "Santiago"
    ],
    "@version.keyword": [
      "1"
    ],
    "docs.Remuneracions.monto_liquido": [
      12000,
      11000
    ],
    "docs.descripcion.keyword": [
      "Pago Remuneraciones"
    ],
    "producto": [
      "lalala"
    ],
    "docs.id": [
      "2"
    ],
...
    "docs.Remuneracions.CartolaDocumento.monto_convertido": [
      12000,
      11000
    ],
    "docs.Remuneracions.Empleado.nombre.keyword": [
      "Alvaro",
      "Santiago"
    ],
    "docs.cargo": [
      23000
    ],
    "docs.Remuneracions.id": [
      "1001",
      "1002"
    ],
    "docs.Remuneracions.Prorratas.cuenta_id": [
      "333333",
      "333333"
    ],
    "docs.Remuneracions.empleado_id": [
      "111",
      "222"
    ],
    "@version": [
      "1"
    ],
    "docs.Remuneracions.CartolaDocumento.cartola_id": [
      "555555",
      "555555"
    ],
    "docs.abono": [
      0
    ],
    "docs.Remuneracions.Empleado.id": [
      "111",
      "222"
    ]
  }
}

Let's say I want to show docs.Remuneracions.monto_liquido of each docs.Remuneracions.Empleado.nombre.keyword (Alvaro, Santiago), meaning it shows alvaro:12000, santiago:11000.
How can I do that? I'm asking because if I create a search like this:

POST /lalala/_search
{
  "size": 0,
  "aggs": {
    "total_por_empleado": {
      "terms": {
        "field": "docs.Remuneracions.Empleado.nombre.keyword"
      },
      "aggs": {
        "total_monto_liquido": {
          "sum": {
            "field": "docs.Remuneracions.monto_liquido"
          }
        }
      }
    }
  }
}

shows 23000 for each (Alvaro and Santiago), instead of 12000 and 11000.
Help!