ترجمة - انجليزي-إسبانيّ - Gently open your heart

The original sounds like song lyrics.

The commas should be:
kokoro wo sotto hiraite, gyutto hiki yosetara
todoku yo, kitto tsutau yo, motto...

The original text is also incomplete, and ends in the middle of a phrase, as the translation shows.

Japanese does not require subjects or objects of verbs. Also, because verbs are not conjugated, there are no hints about who the subject is (as in Spanish or Italian). The translation therefore relies on the context of the utterance, but in this case there is very little information about it. The words in parentheses are tentative, added for clarity.

frase incompleta.
con cuidado = suavemente/dulcemente