This is the 12276th most frequent Korean word.
다하라
"다하라" means "do your best" or "give it your all."
다하라 is used here to signify 'using fully' or 'putting one's complete effort into something.'
심장을 다하라, 그리고 모든 노력에 최선을 다하라.
Use your heart fully, and give your best effort in everything.
다하라 means 'fulfill completely' or 'carry out entirely' regarding responsibilities or tasks.
주어진 임무를 다하라.
Complete the given task.
다하라 emphasizes 'using all of one's strength or capability' in this context.