This is the 17661st most frequent Turkish word.
şirketlerini
"Their companies."
The word 'şirketlerini' here is used in its accusative case, referring to 'their companies' as the object of the verb 'büyütmek' (to grow).
Arkadaşlar şirketlerini büyütmek için yeni stratejiler arıyorlar.
Friends are looking for new strategies to grow their companies.
In this sentence, 'şirketlerini' is the object of the verb 'yönetir' (to manage), indicating possession (their company).
Onlar şirketlerini her zaman en iyi şekilde yönetirler.
They always manage their company in the best way.
Here, 'şirketlerini' is in the accusative case and denotes possession (their company) as the object of the act 'satışa çıkarmak' (to put up for sale).