Should I use switch or if/else for only a select few options?

lets say I have 5 values: "hello", "good bye", "so long", "farewell", "good night"

and i'm looking for 3 values in those 5. should I use switch or if/else. and in this example its 5. but in reality its like 50 values and i am looking for 30 values.

does switch mean that it is only a set amount values and should I just use 3 if else

so basically

if(value = "hello")
  {do stuff}
else if(value = "good bye")
  {try stuff}
else if (value = "so long")
  {act now}

or

switch(value)
  case "hello":
   do stuff
  case "good bye":
   try stuff
  case "so long":
   act now
 default:
   no actions

or

if(value == "hello"){
    do stuff
}
if(value == "good bye"){
   try stuff
}
if(value == "so long"){
   act now
}

i'm getting all 5 values but I only need to act for 3 of those values. now again this is a small example the real world use case has 50 values but I only need to act on 25 to 30 values.