it's not necessary to surround the entire string with the % symbol in a wildcard search. you just need it in the position(s) that you are not specifying the characters to match. if you only want item names that begin with "Simple Defiant", you would only need to match for "Simple Defiant %". if you were trying to find all types of defiant gear, then you would use "% Defiant %".
more info on the subject (and sql queries in general) can be found here:
http://www.w3schools.com/sql/sql_wildcards.asp