> But I Couldn’t download all the contet. When the software 
> finish the download process, I browsed the offline site 
> and all content was missing.

This is generally (99.9%) because of misconfigured scan 
rules. See in 'Set Options'/'Scan rules', you may have to 
authorize httrack to download sites that are not downloaded 
by default ; example of use:
+www.example.com/courses/*