Recently, I built out a quick search widget using the Google Knowledge Graph Search Widget. The widget is a Javascript module that allows you to add topics to your input fields (I've limited mine to People) such as Movies, Places, etc. When a user starts typing, the widget finds a relevant match and it's rendered to the DOM.
In this project, I called the KGSearchWidget() passed in a configuration object, limiting the language, type (here I chose Person) and event handler for selecting an item. In the config variable, I limit the number of results in the dropdown, the language searched, the entity type I want returned and the maximum number of characters in the description of each entity.