will not withhold one's advice or suggestion ❍ 望各位参观者～，以便我们改进。I hope that the visitors will not withhold their suggestions so that improvements will be made.
不吝金玉bù lìn jīn yù
金玉：指宝贵的意见。不吝惜宝贵的意见。not niggardly with gold and gem, not withhold one’s advice or suggestion