This is the 4785th most frequent Russian word.
зарубежных
"Foreign" or "overseas."
Here 'зарубежных' is used as an adjective to describe 'страны' (countries), indicating something related to foreign or overseas.
В университете изучают историю зарубежных стран.
At the university, they study the history of foreign countries.
In this sentence, 'зарубежных' modifies 'компаний' (companies), signifying entities located outside one's own country.
Мы посетили несколько зарубежных компаний для обмена опытом.
We visited several foreign companies to exchange experiences.
Here 'зарубежных' is used to describe 'книг' (books), denoting literature originating from abroad.