Wrong export to Word of Symbol font from Trados Studio 2017

In my documents very often Greek letters apear. When I copy/paste from Word to target any greek letter or any other special symbol selected from Word fonts (I don't know if there exists possibility to change the font directly in Trados), as they should be in the target, they always export to Word as small squares. Then I must correct them all in Word manually what is quite annoying. Does anybody know if there exists any solution to that?