有选择地排除to sift out

• 为了筛除更多的杂质，部分区域对天然气实行二次过滤。

  In order to sift out more impurities, some regions carry out secondary filtering of natural gas.

• “限娱令”是为了限制和筛除扭曲观众审美观的内容。

  Capping the amount of entertainment programmes is aimed at limiting and filtering out content that distorts the aesthetic standard of viewers.