从两张表Eloquent Laravel不在哪里

Question

I have table: User, Certification, Waybill and user_certification and waybill_certification.

I want create query using Eloquent where i check that user have certification which checked in waybill

$check = \App\User::with('certification', 'waybill.certification')->

And i dont now what now, is is possible?

I have create relationship in models

Waybill

  public function certification() {
    return $this -> hasMany('App\WaybillCertification');
  }

  public function user() {
    return $this -> belongsTo('App\User');
  }

User

public function waybill() {
  return $this -> hasMany('App\Waybill');
}

public function certification() {
  return $this -> hasMany('App\UserCertification');
}

I know i could use query builder for it but i would like learn how do it with eloquent.

Recently i used mysqli_query Code:

    $sql = mysqli_query($conn, "SELECT c.ID
    FROM request_certification rc
    INNER JOIN certifications c
    ON rc.ID_certification = c.ID
    WHERE rc.ID_request = '$requestID'
    AND rc.ID_certification NOT IN (
      SELECT c.ID
      FROM certifications c
      INNER JOIN user_certification uc ON uc.certification_id = c.ID
      WHERE user_ID = $userID)");

  if(mysqli_num_rows($sql) > 0) {
    return true;
  } else {
    return false;
  }
}

Thanks for help you.