How to tackle ca final audit

Kapil khanna (Accounts & Audit Executive)   (24 Points)

18 July 2015  
attempted audit may 15 paper & got just 29 marks. It was really surprise for me when I saw such marks bcoz I found 55 marks of answers I have done was correct when I compared it with icai suggested. Professional ethics ,SAs & some of the small chapters can easily fetch us 40 to 45 marks . I dont know what exactly the issue is with my performance or what extra efforts this paper demands.plz guide me