This is the 2845th most frequent Russian word.
автомобилями
"Автомобилями" means "by cars" or "with cars" (instrumental plural of "автомобиль").
In this sentence, 'автомобилями' is used as an instrumental plural form indicating objects being manipulated or used by the subject.
Они управляли автомобилями разных марок.
They were driving cars of different brands.
Here, 'автомобили' (singular form 'автомобиль') appears in the nominative plural case, representing the subject of the sentence.
На стоянке стоят автомобили, покрытые снегом.
There are cars covered with snow in the parking lot.
In this sentence, 'автомобилями' is in the instrumental plural case, reflecting the objects of interest or the point of focus of the verb 'интересуюсь'.