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 textDiv = document.createElement("span");
  const textDivProperties = task._enhanceTextSelection
    ? {
        angle: 0,
        canvasWidth: 0,
        hasText: geom.str !== "",
        hasEOL: geom.hasEOL,
        originalTransform: null,
        paddingBottom: 0,
        paddingLeft: 0,
        paddingRight: 0,
        paddingTop: 0,
        scale: 1,
      }
    : {
        angle: 0,
        canvasWidth: 0,
        hasText: geom.str !== "",
        hasEOL: geom.hasEOL,
      };
  task._textDivs.push(textDiv);
  const tx = Util.transform(task._viewport.transform, geom.transform);
  let angle = Math.atan2(tx[1], tx[0]);
  const style = styles[geom.fontName];
  if (style.vertical) {
    angle += Math.PI / 2;
  }