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):

return pdfDoc.getOpenAction();
        })
        .then(function (openAction) {
          expect(openAction.dest).toBeUndefined();
          expect(openAction.action).toEqual("Print");
          return loadingTask2.destroy();
        });
      await Promise.all([promise1, promise2]);
    });
    it("gets non-existent attachments", async function () {
      const attachments = await pdfDocument.getAttachments();
      expect(attachments).toEqual(null);
    });
    it("gets attachments", async function () {
      const loadingTask = getDocument(buildGetDocumentParams("attachment.pdf"));
      const pdfDoc = await loadingTask.promise;
      const attachments = await pdfDoc.getAttachments();
      const attachment = attachments["foo.txt"];
      expect(attachment.filename).toEqual("foo.txt");
      expect(attachment.content).toEqual(
        new Uint8Array([98, 97, 114, 32, 98, 97, 122, 32, 10])
      );
      await loadingTask.destroy();
    });
    it("gets javascript", async function () {
      const javascript = await pdfDocument.getJavaScript();
      expect(javascript).toEqual(null);
    });
    it("gets javascript with printing instructions (JS action)", async function () {