Hi Nirmala,

As you have completed Bachelors in Economics and Political science From DU , You can pursue Masters in Both universities, But depends on the area of interest and fee structure that fits your budget. Both colleges are equally good as per reviews of students on there official websites.

Korean University - You can choose either -  Graduate Program in Mass and Media or Graduate program in Policy Studies.

Seoul National University - You can choose  - Graduate program in Political Science and International Relations , Graduate program in Business administration or Graduate program in Economics.

Best part of Seoul University is the offer your both graduate and post graduate programs but only if you opt  them. this might reduce your fees structure and time period of both degrees. Better inquire on there official site. Hope this is helpful to you.

Thanks.