How to better in Short Form of Codechef

In long contest i am able to solve 5-6 questions and try others, but i short form of contest specially COOK-OFF i am only to solve the first two then done :frowning: . Even when i see the number of people who have solved 3rd , 4th and 5th question is very few. I am not sure what need to be done to do better here.Any kind of help will be great.