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):

expect(!!data[0].styles).toEqual(true);
      expect(!!data[1].items).toEqual(true);
      expect(data[1].items.length).toEqual(7);
      expect(!!data[1].styles).toEqual(true);
    });
    it("gets text content, with correct properties (issue 8276)", async function () {
      const loadingTask = getDocument(
        buildGetDocumentParams("issue8276_reduced.pdf")
      );
      const pdfDoc = await loadingTask.promise;
      const pdfPage = await pdfDoc.getPage(1);
      const { items, styles } = await pdfPage.getTextContent();
      expect(items.length).toEqual(1);
      
      const fontName = items[0].fontName;
      expect(Object.keys(styles)).toEqual([fontName]);
      expect(items[0]).toEqual({
        dir: "ltr",
        fontName,
        height: 18,
        str: "Issue 8276",
        transform: [18, 0, 0, 18, 441.81, 708.4499999999999],
        width: 77.49,
        hasEOL: false,
      });
      expect(styles[fontName]).toEqual({
        fontFamily: "serif",
        ascent: NaN,
        descent: NaN,
        vertical: false,