I found the staffs were co-operative. I visited embassy to extend Srijana's visa, as her professor denied to extend it. Mr. Khanal, chief of the embassy (I don't know what's his post), I found him very generous person. He called to Srijan's advisor professor and requested to extend her visa.
I talked to Mr. Khannal for 20 minutes. He asked me, my experience in Korean companies, payments and benifits. He talked about his relatives who wanna come to Korea. It was a nice talk.
Srijana finally called her professor, he agreed to extend her visa. We thanked staffs of the embassy and came back.
A nice experience.
* Above picture is the map of the embassy to get there.