Spare no pains to speak.

说话不留余地。

You spare no pains of pay to make this cooperation obtain tremendous success.

你们不辞辛劳的付出才使得本次合作取得巨大成功。

We should spare no pains to construct whole, harmonious and sustained society of harmony in China.

努力构建我国全面、协调、可持续发展的和谐社会。