usredotočiti

1. Croat. (with se, + na + acc.) to concentrate; to focus
   Moramo se usredotočiti na posao. — We need to focus on work.
   Od buke se nisam mogao usredotočiti. — I couldn't concentrate because of the noise.
2. Croat. (+ acc. + na) to concentrate; to focus
   Usredotočio je sve snage na taj zadatak. — He focused all his energy on that task.

In Serbia the words are usredsrediti (se) or koncentrisati (se).