Here, i have attached the PDF, that PDF document contains "Nudi" as an embedded font. When i searching the particular word (that in Nudi font), the search result selecting the word that context next to the exact word.

Link to PDF file (or attach file here):
[sample_pdf.zip](https://github.com/mozilla/pdf.js/files/229582/sample_pdf.zip)

Configuration:
- Web browser and its version: Mozilla 45.0.2
- Operating system and its version: Windows 7
- PDF.js version: 1.4.20-disc

What is the expected behavior? (add screenshot)
![find_01](https://cloud.githubusercontent.com/assets/17423938/14704922/c2e67f2c-07d4-11e6-9320-9aed2578d377.png)

if (
          prevElem.match + prevElem.matchLength >=
          currentElem.match + currentElem.matchLength
        ) {
          currentElem.skipped = true;
          return true;
        }
      }
      return false;
    }
    
    
    matchesWithLength.sort(function (a, b) {
      return a.match === b.match
        ? a.matchLength - b.matchLength
        : a.match - b.match;
    });
    for (let i = 0, len = matchesWithLength.length; i < len; i++) {
      if (isSubTerm(i)) {
        continue;
      }
      matches.push(matchesWithLength[i].match);
      matchesLength.push(matchesWithLength[i].matchLength);
    }
  }
  /**
   * Determine if the search query constitutes a "whole word", by comparing the
   * first/last character type with the preceding/following character type.
   */
  _isEntireWord(content, startIdx, length) {