Backpacking student- proof of funds+visit plans

Hi, I'm a student from Belgium and I was studying in the uk last year, but right now I'm backpacking in SEA. I'm planning to visit china next month and i want apply for an L visa. As a student I don't have a job so no income and I don't have sufficient funds (100 usd/day)on my bank account, however I am backed up by my parents in case in really money. Also as a backpacker I don't have a very detailed plan of what I'm going to be visiting, would hotel bookings be enough or do I really need a day by day plan? Do i really need an invitation letter too? Is it also possible to stay for more than 30 days? I'd like to enter from Vietnam in early may and leave by plane at the end of June.