How to get all the referenced assemblies using reflection ? (.net4)

I've made a piece of code that gives me the referenced assemblies of one assembly (in .net5) and it was working greatly, it gave me for exemple if I use the File.WriteAllText method the assembly "System.IO.FileSystem" (this is by using the Assembly.GetReferencedAssemblies method).

But now I need to get this code to work on .NET4 (for Unity Engine). But i've seen that the myAssembly.GetReferencedAssemblies do not give the same output as in .NET5.

It now gives me only: myAssembly.dll and mscorlib.dll

And I cannot make it work to give me like previously all the referenced assemblies (for exemple System or System.IO ...)

Any idea how to make the myAssembly.GetReferencedAssemblies work on .net4 ? Thanks!