distance function of Google AppEngine Search API is behaving unconsistantly -

    string loc_expr = "distance(location, geopoint(" + userlatitude + ", " + userlongitude + "))";      // build sortoptions     sortoptions sortoptions = sortoptions.newbuilder()             .addsortexpression(sortexpression.newbuilder().setexpression(loc_expr).setdirection(sortexpression.sortdirection.ascending).setdefaultvaluenumeric(0))             .setlimit(200).build();      // build queryoptions     queryoptions options = queryoptions.newbuilder().addexpressiontoreturn(fieldexpression.newbuilder().setexpression(loc_expr).setname("distance")).setlimit(limit)             .setcursor(cursor).setsortoptions(sortoptions).build();      string querystring = loc_expr + " < " + searchradius * 1000;      // build query , run search     query query = query.newbuilder().setoptions(options).build(querystring);      indexspec indexspec = indexspec.newbuilder().setname("restaurants").build();     index index = searchservicefactory.getsearchservice().getindex(indexspec);      results<scoreddocument> result = index.search(query);     if (result.getnumberfound() > 0) {         collection<scoreddocument> coll = result.getresults();          (scoreddocument sd : coll) {             key<restaurant> key = key.create(string.valueof(sd.getid()));             restaurant rest = ofy().load().key(key).now();              field f = sd.getexpressions().get(0);             log.info("distance in meter : " + f.getnumber());         }     } 

i using above mentioned code restaurants in nearby area. following observation :-

case 1: searchradius = 0.5 km --- maximum value of distance = 0.9 km

case 2: searchradius = 1 km --- maximum value of distance = 1.8 km

case 3: searchradius = 2 km --- maximum value of distance = 2.8 km

case 4: searchradius = 3 km --- maximum value of distance = 4.8 km

why getting value of distance more radius specified?

note :- not calculating distance own. distance being returned search api.

it's known issue.

until google fix it, have filter results in code