improving modelling skills (desideratum)

[micheus]

Anybody knows about good tutorials or books to improve modelling skills?

Sorry. I have nothing to suggest.

When modelling I always think it should be another easier way to resolve the model or I tend to use a lot of steps and after time I discover there's a command or a set of commads that do exactly what I've done more complicated

That is very common thought.
There will be always a different way to do something. And that also will depends on the software capabilities and artist's skills
... and you are going to improve your skills by practising, practising and practising. To know the tool you are using is the best way to get the most it can offer you.

Wings3D was designed to be used in Box Modelling Technic. (Box Modeling techniques for getting a perfect 3D model)

Box modeling approach will fit very well to what we hear as "hard surface" modeling nowadays.

You can learn good techniques/approach from any video, tutorial that is focused in box modeling and then apply to your projects in Wings3D - for instance.

I recorded some translations from video tutorials made with other tools which I tried to reproduce the same approach as in the original, but in Wings3D.
In some cases we can find a real tool limitation, in others I knew there were a better and easier way to make it on Wings3D, but in general we can reproduce most of what is done with other 3D apps - talking about the box modeling approach, of course.