What Does "prominent Bronchi Vascular Markings" In An X Ray Indicate?

Hi...I had the flu about 6 weeks ago..cough,sore throat, fever...most symptoms are gone except for a lingering dry cough. I went to the walk in clinic ..X-Ray was recommended, after reviewing with the doctor I was told that I have prominent bronchi vascular markings..possibly chronic. If this continues I may need puffers. I have always been a non-smoker, in good health sever had allergies. I am a 46yrs old male. Can you please explain what would cause this and how to cure this problem? Thanks for your help!!