qulūbihim
their hearts
N – genitive feminine plural noun + PRON – 3rd person masculine plural object pronoun Ha
Root Link: ق ل ب
kānū
they used to
V – 3rd person masculine plural perfect verb + PRON – subject pronoun waw
Root Link: ك و ن
yaksibūna
earn
V – 3rd person masculine plural imperfect verb + PRON – subject pronoun na
Root Link: ك س ب