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 loadingTask.promise
          .then(function (pdf) {
            return pdf.destroy();
          })
          .then(
            function () {
              expect(expectSuccess).toEqual(true);
            },
            function (error) {
              if (expectSuccess) {
                
                expect(error).toEqual("There should not be any error");
              }
              expect(expectSuccess).toEqual(false);
            }
          );
      }
      function testCanLoad(filename, options) {
        return _checkCanLoad(true, filename, options);
      }
      function testCannotLoad(filename, options) {
        return _checkCanLoad(false, filename, options);
      }
      afterEach(async function () {
        if (loadingTask && !loadingTask.destroyed) {
          await loadingTask.destroy();
        }
      });
      it("server disallows cors", async function () {
        await testCannotLoad("basicapi.pdf");