Fadel, you just said.. nothing.

Service is to become effective if well used

Make it in every language

I agree with you about the language but if you can watch sth during game you can also watch this now - it's not a big difference and here you've got more replays

I totally agree with @Buziak_PL. I don't see any relevant point in uploading this kind of clips. Skipping the language barrier, which Buziak_PL aptly noticed, in my opinion the best way of learning volleyball elements is just to watch furtively techniques from players during the matches or, furthermore, watching normal replays in slow (or slower) motion would be also appriopriate if we really want to learn something. It's just my opinion.

What for are these films ? :| We can't understand anything. If we wanna get know something from film, we may just focus on plauers doing these parts od volleyball during match or while watching dilms about them on this site - I'm libero and watching films about Sergio and Igła I noticed few interesting films.
And about flot serve for Polish users there is something much better on Akademia Polskiej Siatkówki