if I type
$ npm search babylonjs
packages are listed (there is no babylonjs@preview packages)
WHY?
if I type
$ npm search babylonjs@preview
No matches found for “babylonjs@preview”
WHY no metches???
How can we list baylonjs@preview with npm search?
Greetings
I have no Idea how npm search works. But if you type npm install babylonjs@preview , then the preview will be installed. So the package is there. So npm might not support searching for versions?
why npm search dosn’t find it ?
Why I would like to know.
Because in future if babylonjs@preview will renamed/changed name, I would like to search and finde version if it is preview or not and its name . …
@Deltakosh
I have no idea why they do not list the preview 
Did you try with @babylonjs/core@preview?
npm search
searches only the names of packages and not the version thus you have to search for babylonjs.
If you want to see all available versions you need to type
npm show babylonjs