{Leyline of Singularity}+{Captain Sisay}+{Deadeye Navigator} if u want more then 1 card each turn
Nope, it won't.
{Leyline of Singularity} turns all nonland permanents legendary. However, permanents only exist in play. A card in your library is not a permanent and thus will not be legendary.
Therefore, {Captain Sisay} still cannot tutor them out. Unless of course the card was already legendary to begin with.
ok thanks