fly to Beijing from Karachi, and then fly from Beijing to Hangzhou, at last take a shuttle coach from the airport to Yiwu directly. Get off in Yiwu.

No direct flights are available from Karachi to Yiwu. There are only conjoint flights with two or three transfers. For convenience, you can transfer at Beijing. One or two direct flights are operating from Karachi to Beijing. For more details, you would better check on the website by yourself.