one of parent (father or mother) can get visa for five long term stay .

Annt, it’s possible for you to apply for an S1 type to enter PRC and then you can get a residence permit which may allow you to stay in PRC for more than 180 days and you can renew the residence permit to stay longer when you child continues to study in PRC.
You need to prepare those documents to apply for the S1 type: an invitation letter from the school, an invitation from your child and copy of his/her passport and residence permit in PRC, and the your child's birth certificate, as well as your physical examination report.
After, submit the application to the embassy of PRC to apply for the S1 type.