Should I stay or quit?

I am working in an IT company since last December and I joined as a intern and after a month got promoted to trainee. The work culture is not that good and I have applied to over 35+ jobs and didn't get response from anyone. I have also asked for the salary increment but they denied and said before 6 months they won't do that. So what would be the better option. To work in unhealthy environment or to quit and work on self. (8 sem engineering student)