Reducing APK size // Levels issue from Editor Log

Hi, I am trying reducing my apk file. I editted my textures and other things.

Also im showing big size in Levels from Editor Logs.

 Textures      165.3 mb     74.6% 
 Meshes        4.3 mb     2.0% 
 Animations    0.0 kb     0.0% 
 Sounds        6.4 mb     2.9% 
 Shaders       1.4 mb     0.6% 
 Other Assets  977.2 kb     0.4% 
 Levels        36.6 mb     16.5% 
 Scripts       1.4 mb     0.6% 
 Included DLLs 5.1 mb     2.3% 
 File headers  135.2 kb     0.1% 
 Complete size 221.6 mb     100.0% 

I tried this methods for reduce Levels' size :

1- I am not using Static Batching 2- I am not using Dynamic Batching. 3- I removed all "resources" folders.

And I found why Levels creating this size. I am using pooling system in my game.

I am adding all vehicles in my game scene. The player choose which vehicle, the car's setActive will true. So i am using this method. if i use this way "Levels" issue giving big size.

Why if i add my vehicle prefabs in the scene with this method the Levels giving big size ? The apk including everything for this prefabs (textures, codes, materials, shaders).

I tried delete objects step by step in the scene when i delete my vehicles in the scene Levels' size reducing...

I