Orginated from hokkien langguage widely use in SINGAPORE. Now the words have spread to their neighbour country MALAYSIA.
Wa-Lau means "Oh my DAD", same meaning of some people say "Oh My GOD". Because the founder was not a religion guy, so instead of using the GOD, it use his own DAD.
Some might use WA-MA! mean "oh my MOM" for those mummy's boy.
And last but not list, the "eh" is just a finishing touch to enchance the words Walau or Wama!
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. PenguinBooks,1992. p. 38)