Program Ignoring if Statements

local joke = 1
local start = 0
term.setBackgroundColor(colors.white)
term.clear()
term.setCursorPos(19,7)
term.setTextColor(colors.blue)
print("Sara v0.2.5")
term.setCursorPos(18,9)
term.setTextColor(colors.red)
print("SYSTEMS OFLINE")
term.setCursorPos(9,13)
term.setTextColor(colors.black)
print("type 'sara on' in chat to power on")
if start == 0 then
local event, right, player, msg = os.pullEvent("chat_message")
  if msg == "sara start up" or "sara power on" or "sara turn on" or "sara on" then
  start = 1
  end
end

c = peripheral.wrap("right")

term.setCursorPos(18,9)
term.setTextColor(colors.purple)
print("SYSTEMS STARTING")

c.setLabel("Sara")
c.say("Powering Up...")
sleep(math.random(2.,5))
c.say("Powerup Complete!")

term.setCursorPos(18,9)
term.setTextColor(colors.green)
print(" SYSTEMS ONLINE ")

while true do

  local event, right, player, msg = os.pullEvent("chat_message")

if msg == "sara hello" or "sara hi" then
  local res1 = math.random(1,2)
  sleep(math.random(0.5,1))
   if res1 == 1 then
   c.say("Hello Sir")
   end
   if res1 == 2 then
   c.say("Hello There")
   end
end

if msg == "sara joke" or "sara tell me a joke" then
  sleep(math.random(1.5,3))

   if joke == 6 then
	c.say("No more Jokes, Restarting from beginning")
	   joke = 0
   end
  
   if joke == 5 then

	   joke = joke+1
   end
  
   if joke == 4 then

	joke = joke+1
   end
  
   if joke == 3 then

	joke = joke+1
   end
  
   if joke == 2 then

	joke = joke+1
   end
  
   if joke == 1 then
	c.say("Can a kangaroo jump higher than a house?")
	sleep(3)
	c.say("Of course, a house doesn't jump at all.")
	joke = joke + 1
   end
  
if msg == "sara enable lamp" then
  c.say("Enabling Redstone on Top Side")
  redstone.setOutput("top", true)
end

if msg == "sara open doors" then
  c.say("Opening Doors")
  redstone.setOutput("left", true)
  sleep(6)
  c.say("Closing Doors")
  redstone.setOutput("left", false)
end

else
  c.say("error")
end

end