you can make like this
function drawText() -- draw text
dxDrawText("You have successfully bought a vehicle!", 92, 158, 720, 195, tocolor(65, 205, 4, 255), 1.40, "pricedown", "left", "top", false, false, true, false, false)
addEventHandler("onClientRender", root, drawText)
setTimer (removeEventHandler, 5000, 1, "onClientRender", getRootElement(), drawText) -- remove text
OR
use Textdisplay