This is how you can nest multiple bool queries in one outer bool query
                        
                        this using Kibana,
                        
                        
                        
                            GET my_inedx/my_type/_search
                        
                            {
                        
                                "query" : {
                        
                                   "bool": {             //bool indicates we are using boolean operator
                        
                                        "must" : [       //must is for **AND**
                        
                                             {
                        
                                               "match" : {
                        
                                                     "description" : "some text"  
                        
                                                 }
                        
                                             },
                        
                                             {
                        
                                                "match" :{
                        
                                                      "type" : "some Type"
                        
                                                 }
                        
                                             },
                        
                                             {
                        
                                                "bool" : {          //here its a nested boolean query
                        
                                                      "should" : [  //should is for **OR**
                        
                                                             {
                        
                                                               "match" : {
                        
                                                                   //ur query
                        
                                                              }
                        
                                                             },
                        
                                                             { 
                        
                                                                "match" : {} 
                        
                                                             }     
                        
                                                           ]
                        
                                                      }
                        
                                             }
                        
                                         ]
                        
                                    }
                        
                                }
                        
                            }
                        
                        
                        
                        
                        
                        
                        
                        This is how you can nest a query in ES
                        
                        There are more types in "bool"
                        
                        like - 1. Filter   2. must_not
                        
                        
                        
                
             
            
                
                    
                        You need an extra `bool filter` between the `must` and `must_not` terms.
                        
                        
                        
                        You should also think about your *myField* field. If it is defined as text or as keyword. 
                        
                        Tested with elasticsearch 5.6.1 the following query works:
                        
                        
                        
                            {
                        
                              "query": {
                        
                                 "bool": {
                        
                                    "must": [{
                        
                                     
                        
                                      "query_string": {
                        
                                         "query": "this is a text content"
                        
                                      }
                        
                                    }],
                        
                                  
                        
                                    "filter": {
                        
                                       "bool": {
                        
                                          "should" : [{                
                        
                                             "bool" : {
                        
                                                "must_not": {
                        
                                                  "exists": {
                        
                                                     "field": "myField"
                        
                                                   }
                        
                                                 }
                        
                                              }
                        
                                          },
                        
                                          {
                        
                                            "bool" : {
                        
                                              "must": {
                        
                                                "terms": {
                        
                                                   "myField.keyword": ["my field exists and has a value"]
                        
                                                 }
                        
                                               }
                        
                                            }
                        
                                          }]
                        
                                       
                        
                                     }
                        
                                  }
                        
                               }
                        
                              }
                        
                            }