I wouldn't be surprised if Amazon tweaked their search engine after the referenced study came out. Maybe even specifically for that word combination. This happ

I wouldn't be surprised if Amazon tweaked their search engine after the referenced study came out. Maybe even specifically for that word combination. This happens a lot. When popular magazines do search tests with a range of apps and one of the result is "$foo didn't find our $absurd_word_that_we_use_for_testing" you can be sure that it will find it soon afterwards so they won't look bad again in later tests.