Asynchtonous JSON request

asyncJson.js

getResults() {
    $.when(
      $.getJSON(universityData.root_url + '/wp-json/wp/v2/posts?search=' + this.searchField.val()),
      $.getJSON(universityData.root_url + '/wp-json/wp/v2/pages?search=' + this.searchField.val())
    ).then((posts, pages) => {
      var combinedResults = posts[0].concat(pages[0]);
      this.resultsDiv.html(`
        <h2 class="search-overlay__section-title">General Information</h2>
        ${combinedResults.length ? '<ul class="link-list min-list">' : '<p>No general information matches that search.</p>'}
          ${combinedResults.map(item => `<li><a href="${item.link}">${item.title.rendered}</a></li>`).join('')}
        ${combinedResults.length ? '</ul>' : ''}
      `);
      this.isSpinnerVisible = false;
    }, () => {
      this.resultsDiv.html('<p>Unexpected error; please try again.</p>');
    });
  }