Chances of good unis?

<p>I currently have my AS grades, which were not that good, Chemistry/Physics: B and Econs: C. I had wanted to go to Seoul Uni, but I completely flunked the tests so I have no idea what I could do to enter Seoul Uni or any other noteworthy universities. Financial situation isn't very good so I wanted to go to a korean uni for cheaper expenditure (have relatives there) would I still be able to enter unis like Seoul Uni if I worked hard and got high marks in my A2?</p>