Code : 
package demo;
import java.util.Scanner;
/**
 *
 * @author www.CodeTheta.com
 */
public class StringSearch {
    public static void main(String[] args) {
        String TextString;
        String FindString;
        System.out.println("Enter a string : ");
        Scanner in = new Scanner(System.in);
        TextString = in.next();
        System.out.println("Enter a word you want to find.");
        Scanner in1 = new Scanner(System.in);
        FindString = in1.next();
        int IndexNumber = TextString.indexOf(FindString);
        if(IndexNumber == - 1) {
            System.out.println("Not Found");
        } else {
            System.out.println("Entered Word Found at Index Number : " + IndexNumber);
        }
   }
}

IDE Used To Test This Code : NetBeans IDE 8.2

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