string[] guids = AssetDatabase.FindAssets(string.Format("t:{0}", typeof(CarInformation)));
        if (guids.Length>0)
        {
            allCars.Clear();
            for (int i = 0; i < guids.Length; i++)
            {
                string assetPath = AssetDatabase.GUIDToAssetPath(guids[i]);
                CarInformation asset = AssetDatabase.LoadAssetAtPath<CarInformation>(assetPath);
                if (asset != null)
                {
                    allCars.Add(asset);
                }
            }
        }