The court investigation order issued by the court of first instance can still be used during the second instance.
However, the second instance court is a retrial court of first instance and has the right to deny the facts obtained by the first instance court’s investigation. Generally speaking, if the facts are unclear and the evidence is insufficient, the first-instance court will remand the case for retrial, or it can directly change the verdict once the facts are found out.
Characteristics of the second instance:
Neither the second instance procedure nor the retrial procedure are necessary procedures for the People's Court to hear civil cases. The retrial procedure is a special trial procedure that does not increase the level of trial. Its characteristic is that the party's application for retrial cannot directly trigger the retrial procedure. That is, whether the party's application initiates the retrial procedure shall be reviewed and decided by the people's court.