Hidden text behind is extracted while visible text is not extracted

I have run the ExtractTextInfoWithCharBoundsFromPDF code for the PDF in this URL:

https://drive.google.com/file/d/14qy_GPS3dzXI-meJiCKkvqwUb59Q1yWk/view?usp=sharing
The following text which is hidden behind the image is extracted: 
ANNUAL REPORT 2018

A text which is actually visible is not extracted:
Xcel Energy became the first public utility to receive

Is it possible to extract only the visible text ?