Multilingual search

Hi,

i’d like to implement multilingual search for different indexes using instantsearch.
It seems like I set the index correctly but search results of index A are being populated while the index is set to B.
I suspect the issue is with start() but not sure how to approach this, here’s a sample of my code:

$(document).ready(function(e){

 var langCode = 'some string';

  var search = instantsearch({
    appId: '',
    apiKey: '',
    indexName: 'index-name',
    query: 'query',
    advancedSyntax: true,
    searchFunction(helper) {

..

      helper.setIndex("index-name" + langCode);
    }
  });

  search.addWidget(
..
    })
  ); 


  var hitTemplate =
..

  var noResultsTemplate =
    ..

  search.addWidget(
..
  );

  search.addWidget(
..
  );

  search.start();
});

Thanks !