Why is it that the UK Kindle store contains French and German editions of some books, but not the original English printing of the same?
Go on. Search for "Star Wars X-wing", or "Tamora Pierce", to give a couple of examples. For added fun try to work out why the second search is showing books that don't appear to have any link to the words "Tamora Pierce".
Semi-related riddle: why is there no "sort alphabetically" option? "Relevance" may as well be called "random" for all the use it is.