private static void findFilesWithText(String stringToFind,
                                        PsiSearchHelper searchHelper,
                                        GlobalSearchScope scope,
                                        final Set<? super PsiFile> resultFiles) {
    final List<String> words = StringUtil.getWordsIn(stringToFind);
    if (words.isEmpty()) return;
    words.sort((o1, o2) -> o2.length() - o1.length());
    for (String word : words) {
      final Set<PsiFile> files = new HashSet<>();
      searchHelper.processAllFilesWithWord(word, scope, Processors.cancelableCollectProcessor(files), true);
      if (resultFiles.isEmpty()) {
        resultFiles.addAll(files);
      }
      else {
        resultFiles.retainAll(files);
      }
      if (resultFiles.isEmpty()) return;
    }
  }
private static void findFilesWithText(String stringToFind,
                                        PsiSearchHelper searchHelper,
                                        GlobalSearchScope scope,
                                        final Set<? super PsiFile> resultFiles)