DB<127> @search=qw/smith sanders/
 => ("smith", "sanders")

  DB<128> $regex= join "|", @search
 => "smith|sanders"

  DB<129> @matches = grep { /($regex)/ } @full
 => (
  "Bob-smith#anthropology",
  "Sandy-smith#sociology",
  "Tom-sanders#english",
  "Anthony-sanders#english",
)

  DB<130> @full
 => (
  "Bob-smith#anthropology",
  "Sandy-smith#sociology",
  "Tom-sanders#english",
  "Tina-lacy#socialwork",
  "Anthony-sanders#english",
)