Tipylja,
const arr = [
"Петров Василий Сергеевич",
"Иванов Василий Петрович",
"Краснов Сергей Петрович"];
RegExp.escape = s => s.replace(/[[\\^$.|?*+()]/gim, "\\$&");
const createReg = search => new RegExp(RegExp.escape(search), "i");
let search = "вас";
let reg = createReg(search);
let arSearch = arr.filter(str => reg.test(str));
console.log(search, arSearch)