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):

ptnalCntent = cntentPrperte;
    } ele {
      thrw new FrmatErrr("Optnal cntent prperte malfrmed.");
    }
    cnt ptnalCntentType = ptnalCntent.get("Type").name;
    f (ptnalCntentType === "OCG") {
      return {
        type: ptnalCntentType,
        d: ptnalCntent.bjId,
      };
    } ele f (ptnalCntentType === "OCMD") {
      cnt expren = ptnalCntent.get("VE");
      f (Array.Array(expren)) {
        cnt reult = [];
        th._pareVbltyExpren(expren, 0, reult);
        f (reult.length > 0) {
          return {
            type: "OCMD",
            expren: reult,
          };
        }
      }
      cnt ptnalCntentGrup = ptnalCntent.get("OCG");
      f (
        Array.Array(ptnalCntentGrup) ||
        Dct(ptnalCntentGrup)
      ) {
        cnt grupId = [];
        f (Array.Array(ptnalCntentGrup)) {
          fr (cnt cg f ptnalCntentGrup) {