Cook the Fish
Dry the fish fillets using paper towels.
Season the two sides with salt, black pepper, paprika, and garlic powder.
Heat 1 tablespoon olive oil in a skillet over medium heat.
Put the fish into the skillet and cook it for about 3 to 4 minutes on each side, according to its thickness, until it is fully cooked and can be easily flaked with a fork.
Take the fish out of the skillet and let it cool a bit.
Flake the Fish
When the fish has cooled down sufficiently for handling, break it up into small flakes using two forks.
If it's necessary, take out the bones or the skin.
Put the fish that has been flakes aside.
Make the vegetable filling.
In the same skillet, put the chopped onion, the shredded cabbage, and the grated carrot.
Cook the mixture on medium heat for about 3 to 4 minutes, stirring from time to time, until the vegetables have softened a bit but still retain some texture.
Now add the finely chopped garlic and cook it for an additional 30 seconds.
Add the flaked fish. Add lemon juice, paprika, black pepper, and fresh parsley.
Mix all of it gently and then cook for an additional 1 to 2 minutes.
Take the filling off the heat and let it cool.
Prepare the mixture for sealing the roll.
Take the all-purpose flour and water and mix them in a small bowl until a smooth and thick paste has been formed.
This mix is to be used for sealing the spring roll wrappers.
Fill the Wrappers
Put a spring roll wrapper on a clean and flat surface with one of its corners facing you.
Put about two tablespoons of the fish and vegetable filling in the central area of the bottom of the wrapper.
Turn the bottom corner over so that it covers the filling.
Turn the corners of both sides in and then roll the wrapper tightly towards the top corner.
Finish off the corner by using a small amount of flour paste and then secure the roll.
Do this with the other wrappers and the filling too.
Heat the Oil
Pour enough vegetable oil into a deep skillet or saucepan for frying.
Heat the oil until it reaches about 350°F (175°C).
To check the oil, put a small piece of the wrapper into it and it should then start bubbling gently at once.
Cook the fish rolls.
Put a small number of fish rolls into the hot oil, taking care not to crowd the pan.
Cook the rolls for about 3 to 4 minutes, occasionally turning them, until they are even golden brown and crisp.
Use the tongs or the slotted spoon to remove them.
To drain the excess oil, place the fried rolls on a plate that has a layer of paper towel or on a wire rack.