I think it's typical of Hitchcock that he introduces a new piece of evidence, but he finds a visual means of doing it, a means that makes the audience look even harder into the screen to squint and figure out his point.
개가 킁킁대며 다닌 곳 말인가요? 땅을 파던 곳 말이야 그 꽃들을 봐요 끝에 있는 노란색 꽃을 봐요