This is the 15137th most frequent Russian word.
полных
"Полных" means "full" or "complete" in English.
Here, 'полных' modifies 'года' to mean 'complete/full years', emphasizing the entirety or completeness of the time.
У меня есть два полных года опыта работы.
I have two full years of work experience.
Here, 'полных' modifies 'бутылок', meaning 'full bottles', indicating the bottles are filled up.
Он купил несколько полных бутылок воды перед путешествием.
He bought several full bottles of water before the journey.
In this case, 'полных' modifies 'три', meaning 'complete/full three', emphasizing the entirety of the shelves taken.