Difference between simple search query and multi match

Hi I am using two search query which is giving similar result. what is difference between these two query simple query string and multimatch?

1- simple_query_string

GET index/_search
{
  "size": 50,
  "query": {
    "bool": {
      "should": [
        {
          "simple_query_string": {
            "query": "text search",
            "fields": [
              "Field1^2",
              "Field2^4",
              "Field3^6",
              "Field4^8",
              "Field5^10", 
              "Field6^12",
              "Field7^14", 
              "Field8^16",              
              "*^.1"
            ]
          }
        }
      ]
    }
  },
   "sort": [
    "_score",
    {
      "Field6.keyword": {
        "order": "desc"
      }
    }
  ]
}

Multimatch query

GET index/_search
{
  "size": 50,
  "query": {
    "bool": {
      "should": [
        {
          "multi_match": {
            "query": "text search",
            "fields": [
              "Field1^2",
              "Field2^4",
              "Field3^6",
              "Field4^8",
              "Field5^10", 
              "Field6^12",
              "Field7^14", 
              "Field8^16",              
              "*^.1"
            ],
            "type": "most_fields"
          }
        }
      ]
    }
  },
   "sort": [
    "_score",
    {
      "Field6.keyword": {
        "order": "desc"
      }
    }
  ]
}