The Sina has been designed to accommodate a wide range of users. If you're having difficulty reaching the handlebars you can adjust the footplates and move them closer to the front of the machine. Refer to step 5 in your assembly manual and you'll see the holes in the footplate (highlighted below) that allow you to set the footplates closer or further away from the handlebars.
If you're too far away, position the pedal toward the front of the elliptical. If you find that you're not stretching far enough then position the pedal toward the rear of the elliptical.