Mutiple should and must in boolean query

Question

Hi I am using below query in nest

                Query<Person>
               .Bool(fd => fd
                   .Must(must => must
                   .Match(m => m
                     .Field("first_name")
                     .Query(p.first_name)
                     .Fuzziness(Fuzziness.EditDistance(2))),
                    must => must
                        .Match(ln => ln
                        .Field("last_name")
                         .Query(p.last_name)
                         .Fuzziness(Fuzziness.EditDistance(2))))

                         .Should(ffn => ffn
                       .Match(m => m
                         .Field("father_first_name")
                         .Query(p.father_first_name)
                         .Fuzziness(Fuzziness.EditDistance(2))))
                          .Should(fln => fln 
                           .Match(m => m
                             .Field("father_last_name")
                             .Query(p.father_last_name)
                             .Fuzziness(Fuzziness.EditDistance(2)))));

and below is json query generated for the same

     {"query":{"bool":{"must":[{"match":{"first_name":
     {"query":"abigail","fuzziness":2}}},{"match":{"last_name":
     {"query":"may","fuzziness":2}}}],"should":[{"match":
     {"father_last_name":{"query":"s","fuzziness":2}}}]}}}

Even though I am passing value for 1st should clause for father_first_name it is only taking last should clause for father_last_name. Ironically if I comment out last should clause for father_last_name and keep 1st should clause it starts taking father_first_name

  Modified nest query with only 1 should clause
  Query<Person>

               .Bool(fd => fd
                   .Must(must => must
                   .Match(m => m
                     .Field("first_name")
                     .Query(p.first_name)
                     .Fuzziness(Fuzziness.EditDistance(2))),
                    must => must
                        .Match(ln => ln
                        .Field("last_name")
                         .Query(p.last_name)
                         .Fuzziness(Fuzziness.EditDistance(2))))

                         .Should(ffn => ffn
                       .Match(m => m
                         .Field("father_first_name")
                         .Query(p.father_first_name)
                         .Fuzziness(Fuzziness.EditDistance(2)))));

Will return

     {"query":{"bool":{"must":[{"match":{"first_name":
     {"query":"abigail","fuzziness":2}}},{"match":{"last_name":
     {"query":"may","fuzziness":2}}}],"should":[{"match":
     {"father_first_name":{"query":"t","fuzziness":2}}}]}}}

How to add multiple should to the query

               .Bool(fd => fd
                   .Must(must => must
                   .Match(m => m
                     .Field("first_name")
                     .Query(p.first_name)
                     .Fuzziness(Fuzziness.EditDistance(2))),
                    must => must
                        .Match(ln => ln
                        .Field("last_name")
                         .Query(p.last_name)
                         .Fuzziness(Fuzziness.EditDistance(2))))
                         .Should(should => should
                       .Match(m => m
                         .Field("father_first_name")
                         .Query(p.father_first_name)
                         .Fuzziness(Fuzziness.EditDistance(2))),
                         should => should.Match(m => m
                             .Field("father_last_name")
                             .Query(p.father_last_name)
                             .Fuzziness(Fuzziness.EditDistance(2)))),
                             should => should.Match(m => m
                                 .Field("mother_first_name")
                                 .Query(p.mother_first_name)
                                 .Fuzziness(Fuzziness.EditDistance(2)))))

Answer 1

You're calling Should(..) twice, with the second invocation overriding the value set in the first. Should takes a params Func<QueryContainerDescriptor<T>, QueryContainer>[] so the invocation should look like similar to your Must() call

client.Search<Person>(s => s
    .Query(q => q
        .Bool(fd => fd
            .Must(must => must
                .Match(m => m
                    .Field("first_name")
                    .Query("first name")
                    .Fuzziness(Fuzziness.EditDistance(2))
                ),
            must => must
                .Match(ln => ln
                    .Field("last_name")
                    .Query("last name")
                    .Fuzziness(Fuzziness.EditDistance(2))
                )
            )
            .Should(should => should
                .Match(m => m
                    .Field("father_first_name")
                    .Query("father first name")
                    .Fuzziness(Fuzziness.EditDistance(2))
                ),
                should => should
                    .Match(m => m
                        .Field("father_last_name")
                        .Query("father last name")
                        .Fuzziness(Fuzziness.EditDistance(2))
                    )
                )
            )
        )
    );

With operator overloading, this can be shortened to

client.Search<Person>(s => s
    .Query(q => q
        .Match(m => m
            .Field("first_name")
            .Query("first name")
            .Fuzziness(Fuzziness.EditDistance(2))
        ) && q
        .Match(ln => ln
            .Field("last_name")
            .Query("last name")
            .Fuzziness(Fuzziness.EditDistance(2))
        ) && (q
            .Match(m => m
                .Field("father_first_name")
                .Query("father first name")
                .Fuzziness(Fuzziness.EditDistance(2))
            ) || q
            .Match(m => m
                .Field("father_last_name")
                .Query("father last name")
                .Fuzziness(Fuzziness.EditDistance(2))
            ))
        )
    );