The search box is an integral part of Nutritics, and is always located in the top left of the screen when logging a diet or activity diary, creating a meal plan or creating a recipe.
Press F3 or click the search box to begin searching. Results are returned once you click enter, matching the exact character string to foods, activities, descriptions and keywords in the database. There will be some cached results shown before clicking enter that will show recently used items in your account for easy access. You can switch this off from Settings>Preferences. The search is ranked in order of popularity.
A category filter appears at the top of the search results following a search. Click on a category to refine the results to that category only: