Some people want to increase the powers of Scotland because they do not have control over a reserved power such as foreign policy. Foreign policy is when Westminster takes charge of policies in relation to trade. For example, Hamza Yousaf cannot make new trade deals just for Scotland, he must negotiate these through the UK Government. He was not been able to affect the Brexit deal. This means that the Scottish Parliament, in some people eyes, is not powerful enough and Hamza Yousaf would rather make decision for Scotland.