Typeahead and bloodhound post request not working in Laravel 5

This is my HTML Code:

<input autocomplete="off" type="text" id="chiefComplaintInput" name="chiefComplaintInp" class="typeahead-chiefcomplaint form-control input-circle-right" placeholder="Chief Complaints">

This is my Jquery bloodhound and typeahead code:

var chiefComplaints = new Bloodhound({
    datumTokenizer: function(resp) {
        return Bloodhound.tokenizers.whitespace(resp.value);
    },
    queryTokenizer: Bloodhound.tokenizers.whitespace,
    remote: {
        wildcard: '%QUERY',
        url: "/opd/searchChiefComplaints/",
            transform: function(response) {
                return $.map(response, function(restaurant) {
                    return { value: restaurant.name };
                });
            }
        }
});

$('input#chiefComplaintInput').typeahead({
    hint: false,
    highlight: true,
    minLength: 2,
    limit: 10
},
{
    name: 'chiefComplaints',
    display: 'value',
    source: chiefComplaints,
    templates: {
            header: '<h4 class="dropdown">Restaurants</h4>'
    }   
});

This is the routes that i ahve defined:

Route::get('opd/searchChiefComplaints/{queryParam}', 'OpdController@searchChiefComplaints');

This is the controller code:

public function searchChiefComplaints(Request $request)
  {
    // return Response::json($request->get('queryParam'));
    return $request->get('queryParam');
  }

What i am trying to achieve is that i want to send post request to the controller and receive the JSON in response. Bu i am having problem attaining it i dont know where my code is going wrong :(

via Chebli Mohamed