User blog comment:Lord Loss/Monster Appreciation Day: Lao-Shan Lung and Shen Gaoren/@comment-4894529-20120303182616/@comment-1011548-20120303211934

If they're fleeing you basically need to increase your damage. Get an attack boost from the Felyne Kitchen before the quest, drink a Demondrug, get Attack Up or Reckless Abandon armor skills if possible.

I know you mentioned LS, but I find Anvil Hammer works wonders at Low Rank.