how to increase return size of yahoo related Suggestions php

I have this code that will return keyword suggestion from yahoo using the api.

function suggestion($keyword,$keyid){
        $search_key= str_replace(' ','+',$keyword);
        $app ="D4FRJzjeHUCoJsYIeYV4E6XFUlJpX.o1TWALuI-";
        $search = "http://search.yahooapis.com/WebSearchService/V1/relatedSuggestion?appid=".$app."&query=".$search_key."&output=json";
        $content= file_get_content开发者_如何转开发s($search);
        $json = json_decode($content); 
        foreach($json->ResultSet->Result as $string){
            //insert to database
                 echo $string."<br />";
        }
    }

but it only return 4 keyword suggestion. I tried adding &results=30 in the search, but no luck it still return 4 keyword suggestion only. Thanks a lot.

read the docs, http://developer.yahoo.com/search/web/V1/relatedSuggestion.html

its being shut down in a month, why bother using it now.