You can't apply for Z visa if you are not employed because you can't provide the required documents for Z visa application. You can first apply for China Travel Visa(https://www.travelchinaguide.com/embassy/visa/tourist.htm) and go to China to find a job, but the visa is generally permits 30 days stay duration, you have to find a job in a short time. After you sign the work contract, your employer will organize the documents for you, such as Alien Work Permit and Visa Notification Form, you have to exit Mainland China to wait for the two documents and apply for Z visa.