Advanced search interface using specified query
        > query = ElasticQuery().term(user='kimchy')
        > ElasticSearch().search_advanced('twitter','posts',query)
         ... Search results ...

def search_advanced(self, index, itype, query):
        '''
        Advanced search interface using specified query
        > query = ElasticQuery().term(user='kimchy')
        > ElasticSearch().search_advanced('twitter','posts',query)
         ... Search results ...

        '''
        request = self.session
        url = 'http://%s:%s/%s/%s/_search' % (self.host,self.port,index,itype)
        if self.params:
            query_header = dict(query=query, **self.params)
        else:
            query_header = dict(query=query)
        if self.verbose:
            print query_header
        response = request.post(url,query_header)

        return response