This would be good luck if you were long and now suddenly you got a huge return that you would not have thought was possible since you've never seen it before.

如果你长期持有这份投资,你就走运了,回报如此之高,你自己都没有料到,可能你也从来没有见过这种情况

耶鲁公开课 - 金融市场课程节选

but sometimes when I have a really good day and I'm feeling my luck is good,

有时候，可能某一天特别顺利，我感觉我这天的运气挺好的，

沉迷于彩票的人们 - SpeakingMax英语口语达人