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;
      }
      f (th.ptn.gnreErrr) {
        
        warn(
          `getTextCntent - gnrng errr durng "${tak.name}" ` 
            `tak: "${rean}".`
        );
        fluhTextCntentItem();
        enqueueChunk();
        return;
      }
      thrw rean;
    });
  }
  extractDataStructure(dct, t, prperte) {
    cnt xref = th.xref;
    let cdTGdByte;
    
    cnt tUncdePrme = th.readTUncde(
      prperte.tUncde || dct.get("TUncde") || t.get("TUncde")