SPARQL query get GUIDs by Trefwoord

guidsByTrefwoord.php

<?php
header("Content-type: text/json");

$trefwoord = $_GET["trefwoord"];

$sparqlquery = '
PREFIX veld: <http://archief.io/veld#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
SELECT distinct * WHERE {
  ?sub veld:THWTW "'.$trefwoord.'" .
  ?sub rdfs:label ?label
  BIND(REPLACE(str(?sub), "http://archief.io/id/", "") AS ?img)
} LIMIT 100';

$url = "https://api.data.netwerkdigitaalerfgoed.nl/datasets/mi2rdf/mi2rdf/services/mi2rdf/sparql?query=" . urlencode($sparqlquery) . "";

// does not like url parameters, send accept header instead
$opts = [
    "http" => [
        "method" => "GET",
        "header" => "Accept: application/sparql-results+json\r\n"
        // "header" => "Accept: text/csv\r\n"
    ]
];

$context = stream_context_create($opts);

// Open the file using the HTTP headers set above
$response = file_get_contents($url, false, $context);

// echo $response;
// die();

$json = json_decode($response, true);

$items = [];
foreach ($json['results']['bindings'] as $row) { 
  $items[] = $row['img']['value'];
}

echo json_encode($items);

die();


?>