Offering a 4 rakaat sunnah prayer in the Hanafi madhab

[Khali]

Why is it that the four rakat sunnah of Zuhr, both the sunnas before and after Jumu`ah are offered as four rakats with one salam, and that otherwise one is not considered having offered the sunnah if they are offered as two sets of two rakaat ?

Does this also counts for the four rakaat before Asr and Isha ? And what about the four rakaat after Isha ?

['Abdullaah]

And what about the four rakaat after Isha ?

Four raka'at after 'Isha?

[Khali]

Four raka'at after 'Isha?

Praying 4 rakaats AFTER the fard of salaat al Isha is mentioned in ahadith. Its mentioned that the virtue is that one will gain reward as having prayed these four rakaats on Laylat al Qadr.

There are both Marfu and Mawquf reports regarding this.

[moosa3]

وعليكم السلام ورحمه الله وبركاته

Sunnah after dinner 2 rakaat .. And the Hadith indicates mustahabb ..
Vicu separate from the sunnah .. And pray 2 rakaat Voluntary and not Sunnah ..