I have a sunflower allergy, probably from feeding the birds, that gives my true allergy symptoms of closing throat and intolerance with tachycardia symptom. I wasn't tested for it, but I react if I eat a little.
My blood test is positive for peanut, but I can eat peanut butter just fine, love it.
Sensitivities and intolerances can be just as deadly or severe as true allergies.
Peanuts and sunflower seeds should be listed on labels. Sunflower oil generally doesn't cause a reaction because there's hardly any protein or other allergen in the oil. Many products use a variety of oils and you can't tell for sure from the label what's in it.
There are more allergens you can be skin tested for. What was the reason for testing?
There are lots of things for which there is no standardized or reliable test. Keeping a good food journal (use the search box for the posts) is useful.