Toshie Yoshikuni

My name is Toshie Yoshikuni. My family name is "Yoshikuni". "Yoshi" means"good luck". "kuni" means"country".
My first name is "Toshie". It's written in hiragana, with no kanji. My grandmather asked a fortune teller. The fortune teller said, "Toshie is a good name." But we don't know why.