how to make a spatial query with lucene syntax in elastic search

Question

I am using Titan with Elastic search. titan supports the lucene query syntax but I couldn't find information how to use it with spatial.

I want to look for documents matching a text AND are within given distance. let's say the geofield is called location.

queryString=text:("random") AND location:??? 

note that I am not using ES java libraries or anything else, just titan's indexQuery function which takes a string with a lucene compatible query.

thanks