Все выводит. Как в примере
package com.javarush.task.task19.task1918;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
/*
Знакомство с тегами
*/
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
FileReader fileReader = new FileReader(reader.readLine());
reader.close();
Scanner scanner = new Scanner(fileReader);
StringBuilder HTMLSTring = new StringBuilder();
while (scanner.hasNext()) HTMLSTring.append(scanner.nextLine());
fileReader.close();
Document html = Jsoup.parse(HTMLSTring.toString());
System.out.println(html.body().getElementsByTag(args[0]).toString());
}
}