> I feel like I must find a work not related to computer science

I'm not sure if you've already tried this, but in addition to applying to jobs related to your side project I suggest applying to other jobs that have a lot more jobs available. My guess would be the number of jobs for mobile game dev might be limited and competitive and that would make it difficult when applying as a recent graduate. Web technologies whether for front-end or backend development are greatly in demand and are worth considering.