hi i am indian national lives in poland last 25 years and i have permanent resident card of poland.i

You want to do business in China? If so, you can try to apply for a multiple entry M type. But it is not assured that you can get it in the end. The embassy has the final right to decide the time your entries.

For documents, you need to prepare your valid passport, an application form with a recent taken photo and an invitation letter from your Chinese partner.