Romania has a rapidly expanding job market. Jobs are available with immediate start in virtually every field. You can easily apply with your CV on the most popular job websites or listen to recommendations from your friends or professors. As an international student in Romania, you do not require a working permit, as long as you hold a residence permit for studying in the country. Non-EU students are allowed to work 4 hours/day, without the need to apply for a separate working permit. If you like to work more than 4 hours/day, you should apply for a work permit.
Linkedin.com is a good portal to contact employers directly. There are also many career fairs organised in every major city in Romania and advertised at your university.