Can you silence a spell? (i.e. Eldritch Blast, Thunderwave)

I’m going to multiclass as a Rogue Warlock, and I thought it’d be fun to use Eldritch Blast (Eldritch Spear) as a sort of sniper weapon. Is there some ability/item that allows you to silence spells, or are most spells like EB quiet enough to be stealthy?