Question
How to keep Tulip stay longer and bloom at the vase. Should I cut off leaves to reduce water vapor.

Answer
Tulips are very cool in so much as they are the only flower to keep growing even when cut and in the vase!

Removing the leaves will help the water stay clean, which in turn will help the flower last longer... but the leaf in and to itself doesn't prolong or shorten the life of the tulip.