How to get rid of sum_other_doc_count in aggregations?

Elastic Stack Elasticsearch
1

I am running an aggregation to see what document types does my 'documents' index has (documentType is the field that has the type):

GET my_documents/_search
{
  size: 0,
  "aggs": {
    "dataTypes": {
      "terms": {
        "field": "documentType"
      }
    }
  }
}

I get results like:

"aggregations": {
    "dataTypes": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 41,
      "buckets": [
        {
          "key": "pdf",
          "doc_count": 63
        },
        {
          "key": "msw8",
          "doc_count": 59
        },
        {
          "key": "pdf_archive",
          "doc_count": 11
        },
        {
          "key": "msw12",
          "doc_count": 10
        },
        {
          "key": "mdoc55",
          "doc_count": 9
        },
        {
          "key": "excel8book",
          "doc_count": 7
        },
        {
          "key": "crtext",
          "doc_count": 6
        },
        {
          "key": "maker55",
          "doc_count": 5
        },
        {
          "key": "excel12book",
          "doc_count": 4
        },
        {
          "key": "excel12bbook",
          "doc_count": 2
        }
      ]
    }
  }

I know for a fact that there are some other values in that field that are not listed (I see those values in the regular search); also sum_other_doc_count is not zero which tells me that it's not showing everything. My question is - how do I make it show all values in the resulting aggregation?