Boil the chicken breast and shrimp until cooked, then set aside.
Julienne the cucumber, bell peppers, and onion thinly.
Shred the boiled chicken breast into bite-sized pieces and remove the shells from the shrimp.
In a bowl, combine chicken breast, shrimp, and vegetables. Mix well.
Make a dressing with lemon juice, olive oil, salt, and pepper. Pour over the salad and toss lightly.
Chill in the refrigerator, then plate to serve.