Pour the vegetable broth into a large pot. Add the barley, carrots, celery, tomatoes, zucchini, garbanzo beans, onion, and bay leaves. Season with garlic powder, sugar, salt, pepper, parsley, curry powder, paprika, and Worcestershire sauce. Bring to a boil, then cover and simmer over medium-low heat for 90 minutes. The soup will be very thick. You may adjust by adding more broth or less barley if desired. Remove bay leaves before serving.