Pdf.js (for node) not rendering entire contents of pdf

I am trying to search the text of of a pdf using https://www.npmjs.com/package/pdfjs-dist-for-node.

My code looks like this:

 gettext: function(){
     var data = '../static/example.pdf';
         return pdfjs.getDocument(data).then(function(pdf) {
     var pages = [];
     for (var i = 0; i < pdf.numPages; i++) {
                 pages.push(i);
     }
     return Promise.all(pages.map(function(pageNumber) {
                 return pdf.getPage(pageNumber + 1).then(function(page) {
         return page.getTextContent().then(function(textContent) {
                         return textContent.items.map(function(item) {
             return item.str;
                         }).join(' ');
         });
                 });
     })).then(function(pages) {
         return pages.join("\r\n")
     });
         }).then(function(pages){
     console.log(pages)
     });


 }

This seems to work, but it skips parts of the text. Specifically, it skips whatever I can't highlight with the mouse in the original pdf doc. Is there a way to get pdf.js to pick up on this data?

via David J.