After filing the case, can the court open a culvert for the plaintiff to inquire?

No, your attorney can and does not need court authorization.

The "Criminal Procedure Law" stipulates that lawyers, as litigation participants, have the right to review the case. The defense lawyer's review does not require the approval of the case handling agency. The defense lawyer can review, excerpt, and copy the case starting from the date of review of the prosecution by the People's Procuratorate. Litigation documents and technical appraisal conclusion materials. Defense lawyers may review, excerpt, and copy case materials charging criminal facts from the date the People's Court accepts the case. When a lawyer is entrusted to review files or meet with a criminal suspect, he must bring his lawyer's practicing certificate, law firm certificate and power of attorney or official legal aid letter.

Participants in civil litigation, that is, litigants (plaintiffs, defendants, third parties) and litigation agents, as well as interested parties unrelated to the case, are not allowed to consult court files.