How to enter back into China

Hi, i was born in china but my parents and I left china when I was 6 years old and got overseas passport now. Now I just finished my studies in Australia and is planning to start my career life in China. My parents are currently retiring in China (I do not know what visa they are under - think they have to renew their stay every 1 or 2 years something like that). For my case, can I somehow claim my chinese citizenship back? for my case, is it easier for me to get at least permanent residency visa in China? please help