How to search last occurance of a substring inside a substring?

JAVA Program

public class SearchlastString {
	public static void main(String[] args) {
		String strOrig = "Hello world ,Hello Reader";
		int lastIndex = strOrig.lastIndexOf("Hello");
		if(lastIndex == - 1) {
			System.out.println("Hello not found");
		} else {
			System.out.println("Last occurrence of Hello
         is at index "+ lastIndex);
		}
	}
}

Output

Last occurrence of Hello is at index 13