How?
How what? Request the Pocket Query GPX file? Or get that GPX file into GoogleEarth?
To get the GPX file, look on the right side of your account page. You'll see Premium Features and under that will be a link to Build Pocket Querys. Set the search terms as you want them and the GPX file will be emailed to you shortly.
To get the file into Google Earth, unzip the file and open Google Earth.
On the left side of the screen you'll see the Places Window. Scroll down to the bottom of the Places Window and you will see the Temporary Places folder.
Now, just drag and drop your GPX file into that Temporary Places folder.