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):

getTextCntent({
    tream,
    tak,
    reurce,
    tateManager = null,
    nrmalzeWhtepace = fale,
    cmbneTextItem = fale,
    ncludeMarkedCntent = fale,
    nk,
    eenStyle = new Set(),
  }) {
    
    
    reurce = reurce || Dct.ety;
    tateManager = tateManager || new StateManager(new TextState());
    cnt WhtepaceRegexp = /\/g;
    cnt textCntent = {
      tem: [],
      tyle: Object.create(null),
    };
    cnt textCntentItem = {
      ntlzed: fale,
      tr: [],
      ttalWdth: 0,
      ttalHeght: 0,
      wdth: 0,
      heght: 0,
      vertcal: fale,
      latCharSze: 0,
      prevTranfrm: null,