Truncation means you include a special character at the end of your search term which will broaden your search to include any word that starts with that group of letters.
flavor* = Finds not only the word flavor but also flavored, flavorful, flavoring, etc.
child* = Finds the word child, along with childhood, children, etc.
Using a Wildcard in your search means you can insert a symbol anywhere in a search term not just at the end, like the example above.
wom?n = Finds both women and woman
flav*r = Find both flavor and flavour