Difference in nugets processing via `dotnet add package ..` vs nugets adding via visual studio UI

I need to use native c libraries in my library(that supports several CoreTFs and .net framework) which is published via nuget. I configured it via .csproj file and runtimes folder. But I noticed that when I consume my NuGet via dotnet add package .. in some cases, the native libraries are not copied into the expected folder after consuming, however when I use the VS UI Nuget package manager->Manage Nuget Packages for Solution, all files are placed into correct places.
So, I assume that Nuget package manager makes more steps than just call dotnet add package .., but it's unclear what exactly happens, any help will be appreciated.