Help! I am wondering what to call embossed parts of clouds.

[Hoojania]

Hello
I am a screenwriter intending to write my last script in English.
A part of the story takes place on the infinite expanse of the cloud, and one of the most frequent scenes in this part is the protagonist sleeping among the embossed parts of the cloud at the night.
I am wondering what to call embossed parts of clouds.
Dictionaries suggest Raks, ridges, heaps and piles.
Which one is better?

The other part of the story happens in the empty place between Locomotive of a train and the wagon.
Please tell me if this part of the train has a special name.

 

[Tarheel]

I'm guessing you mean you're writing your next script in English.

The hero of the story sleeps on a cloud at night?

There are embossed parts of a cloud?

 

[jutfrank]

I guess we're all wondering what an embossed part of a cloud is.

 

[Tdol]

Could you link to a picture that shows what you have in mind?

 

[bubbha]

puffs?
billows?

 

[Tdol]

I've looked at skies in many parts of the world, and have not noticed the embossed bits.

 

[emsr2d2]

I'm looking forward to the OP coming back to this thread to explain. I've spent half the morning wondering what the embossed part of a cloud could possibly be.