Zhou Yun's answer clearly couldn't satisfy Yao Yuanfeng.
But Yao Yuanfeng couldn't force Zhou Yun—at such a time, Yao Yuanfeng was too busy trying to please Zhou Yun, let alone do that.
However, Zhou Yun clearly sensed Yao Yuanfeng's dissatisfaction.
She felt that she had not outright rejected him, which was quite respectful to Yao Yuanfeng. It was only when she talked to Song Chi about this matter and mentioned her doubts that Song Chi explained to her the reason behind Yao Yuanfeng's dissatisfaction.