How can I get a Customer list by a list of a Custom String Field?

Hi,
I have a list of ids(each id is a StringCustomField) and I want to iterate through those ids and fetch a list of customers.
But It does not work. In the response, I get only 1 customer.
This is the way I search :

         CustomerSearchBasic customSearch = new CustomerSearchBasic();          SearchCustomFieldList custFieldList = new SearchCustomFieldList();          List<SearchCustomField> searchCustomfieldList = new ArrayList<>();          //search by id          for (String id : idList) {              if(id != null) {                  SearchStringCustomField searchStringCustomField = new SearchStringCustomField();                  searchStringCustomField.setScriptId(idFieldName);                  searchStringCustomField.setSearchValue(id);                  searchStringCustomField.setOperator(SearchStringFieldOperator.IS);                  searchCustomfieldList.add(searchStringCustomField);              }          }          custFieldList.setCustomField(searchCustomfieldList);          customSearch.setCustomFieldList(custFieldList);          return customSearch;