Kevin Vincent, 44, of Arlington, Va., said his wife buys store brand acetaminophen and he wanted to find out more about the problem.
Kevin Vincent's wife purchases generic brands.
Store brand and generic brand are synonymous.  The system was likely confused by this.
( z1 purchase :ARG0 ( z2 person :ARG0-of ( z3 have-rel-role :ARG1 ( z4 person :name ( z5 name :op "Kevin" :op "Vincent" ) ) :ARG2 ( z6 wife ) ) ) :ARG1 ( z7 brand :mod ( z8 generic ) ) )