# Put something as stone or etc. on the floor of the pressure cooker for making the colander not stay on the floor, and place the metal colander on it. (If you don’t have an available colander for that you can also use a grater for instead of it.)
# Pell the 
carrots, 
potatoes and celeries and place into the colander. 
# Add water, but it would not reach to the vegetables.
# Cover the lid of the pressure cooker, and cook for 10 more minutes after it reaches to the boiling point.
# Let the vegetables cool down in the pressure cooker, and then chop them into 
hazelnut sized pieces.
# Place the chopped vegetables on the service plate, and then add the finely sliced 
onion and parsley, mix.
# Drizzle salt and pour 
lemon juice and 
olive oil all over.
# Refrigerate for 1 hour and serve.