Um, just in case you don't realize, "-1" selects pages that don't include "1". You just asked Google for pages that both include and don't include "1", and that

Um, just in case you don't realize, "-1" selects pages that don't include "1". You just asked Google for pages that both include and don't include "1", and that's the empty set. I'm not aware of any way to search for negative numbers. This is really a UI problem. Google should probably use the context in this query to infer that you didn't literally want to exclude "1" from your results. However, half the comments here are complaining about Google not taking their queries extremely literally. This problem is a good demonstration of why inferring user intent can be useful and taking user input literally all the time is not actually a great idea.