Thank you. The behaviourist told me about this thing with umbrella but never try it.
 At anti social class, all the dogs are muzzled and on lead at first, after that off lead all the dogs so they can interact with other. 
He is going to day care one day per week, every weekend we go in big park but in week time we walk just around the house where he doesn't meet dogs everyday.
When we are in park i let him off lead around small dogs but he still agressive even if the dog is not jumping on him.
He met the most shy yorkie girl, they had no contact at all. She was in the house with us for 2 days. This I find it weired

) and when by mistake the yorkie girl came a bit closer to him, he snapped. 
I try to do my best for him. I know he is not happy like that. He loves being outside, in parks. Would love to see him again mixing with dogs and play like he did before. 
Thank you for your messages and for our care