I committed the crime of intentional injury when I was a minor, and now my file is sealed. Property management companies need to extract fingerprints. Will it find my file?

No, I can't find it. If the criminal record is sealed, it shall not be provided to any unit or individual, except for the need of judicial organs to handle cases or the relevant units to make inquiries in accordance with state regulations.

Criminal procedure law

Article 275 If a person was under the age of 18 at the time of committing a crime and was sentenced to fixed-term imprisonment of not more than five years, his criminal record shall be sealed.

If the criminal record is sealed, it shall not be provided to any unit or individual, except for the need of judicial organs to handle cases or the relevant units to make inquiries in accordance with state regulations. Units that inquire according to law shall keep the sealed criminal records confidential.