Sobhan,
This is a Eevee limitation at this time that a refracted object behind a refracted object would not be visible. See image from Definitive Interiors course with my realistic glass shader from @chippwalters.:
The glass in front is using refraction. The glass behind on the left is using refraction and notice that it is partially occluded because of the Eevee limitation that refracted objects behind an refracted object are not visible. Now look at the glass behind on the right it is using transparency instead of refraction and it is not occluded, and still looks good.
To allow object behind a refracted object to be visible using my realistic glass shader replace the glass BSDF node with a transparent BSDF node. You will loose refraction and gain transparency for the object behind and still get really nice reflection. Remember that getting good reflection is the key to having great looking glass.
Depending on your scene having glass with transparency instead of refraction may be more important for objects behind as long as your getting good reflection. Most of the time I use refraction for objects behind, but other cases transparency for the objects behind works best like in the scene above.
Look at my previous post in this thread and you will find plenty sample scenes I have posted. Except for the Chocofur and Evermotion scenes. This ones you will find tips and techniques in how I converted to Eevee in my thread on Eevee ArchViz see link Realistic ArchViz.