If the training content agreed in your training agreement is internal training, and the employer fails to provide evidence to prove the training fee expenditure, and there is no basis for asking for deducting the training fee, you can request arbitration to return the deducted salary. General arbitration will support it.
Labor Contract Law
Article 22 Where an employing unit provides special training fees and professional technical training for laborers, it may conclude an agreement with the laborers to stipulate the service period.
If the laborer violates the service period agreement, he shall pay liquidated damages to the employer in accordance with the agreement. The amount of liquidated damages shall not exceed the training expenses provided by the employer. The liquidated damages that the employer requires the laborer to pay shall not exceed the training expenses that should be shared for the unfinished part of the service period.
If the employer and the employee agree on the service period, it will not affect the employee's improvement of labor remuneration in accordance with the normal wage adjustment mechanism during the service period.