What subject of social science best for postgraduation in japan? -

i am doing undergraduation in journalism from dhaka university, bangladesh. if i want to do post graduation from japan, what subject/courses should i chose to get good jobs there afterward. any body advise would be praised much.

http://www.studyjapan.go.jp/en/index.htm... http://www.jpss.jp/eng/index.html http://www.jasso.go.jp/study_j/sgtj_e.ht... http://www.japan-guide.com/e/e2232.html