Can Lua's require function return multiple results?

You could always return a function from your module and have that return multiple values, like below:

foo.lua

return function() return "abc", 123 end

bar.lua

local a, b = require "foo" ()

Lua 5.1.3
require lua export implemented in static int ll_require (lua_State *L) in loadlib.c file. This functions always returns 1 as number of returned values on stack.