[Белый шум]

var str = [' - Learn _ in - 111', 'x - Learn x in - 22', 'xyz - Learn xyz in - 3', '44444'];
for (i in str) {
    s = str[i].match(/^(?:[^\s-]*?)([^\s-])?(?:[\s-]+)(.+)$/);
    s && alert(JSON.stringify('1: ' + s[1] + ',  2: ' + s[2]));
}