Attach (recommended) or Link to PDF file here:
[Hong Kong Aircraft Engineering Company Limited_1511417616.1 2.pdf](https://github.com/mozilla/pdf.js/files/1539395/Hong.Kong.Aircraft.Engineering.Company.Limited_1511417616.1.2.pdf)


Configuration:
- Web browser and its version: Chrome: 63 
- Operating system and its version: windows and macOs
- PDF.js version: 2.0.185
- Is a browser extension: No

Steps to reproduce the problem:
1. Upload the above PDF and search for "article 1"
2. PDF.js showing only **2** match But actually **4** times available.   

What is the expected behavior? (add screenshot)

![screen shot 2017-12-07 at 7](https://user-images.githubusercontent.com/6101789/33720106-ed404576-db88-11e7-9c19-cf6aea74e9f3.png)



What went wrong? (add screenshot)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

const basicApiFileName = "basicapi.pdf";
  const basicApiFileLength = 105779; 
  const basicApiGetDocumentParams = buildGetDocumentParams(basicApiFileName);
  let CanvasFactory;
  beforeAll(function () {
    CanvasFactory = new DefaultCanvasFactory();
  });
  afterAll(function () {
    CanvasFactory = null;
  });
  function waitSome(callback) {
    const WAIT_TIMEOUT = 10;
    setTimeout(function () {
      callback();
    }, WAIT_TIMEOUT);
  }
  describe("getDocument", function () {
    it("creates pdf doc from URL-string", async function () {
      const urlStr = TEST_PDFS_PATH + basicApiFileName;
      const loadingTask = getDocument(urlStr);
      expect(loadingTask instanceof PDFDocumentLoadingTask).toEqual(true);
      const pdfDocument = await loadingTask.promise;
      expect(typeof urlStr).toEqual("string");
      expect(pdfDocument instanceof PDFDocumentProxy).toEqual(true);
      expect(pdfDocument.numPages).toEqual(3);
      await loadingTask.destroy();
    });
    it("creates pdf doc from URL-object", async function () {
      if (isNodeJS) {
        pending("window.location is not supported in Node.js.");