- set\ one's\ heart\ on\ doing\ smth
- v. phr.To want very much.
He set his heart on that bike.
To be very desirous of; hope very much to succeed in. - Used with a verbal noun.He set his heart on winning the race.
Словарь американских идиом. — СПб., Изд-во "Лань". Оригинал: A.Маккей, М.Т.Боткер, Дж.И.Гейтс. 1997.