foreign matters

基本解释

We have also introduced a new processing machine to separate tiny foreign matters from the roasted coffees.
我們更引進一台設備用以分隔混在咖啡豆內的外來物質。
chinafanyi.com
The filtering device can filter the foreign matters in the water while washing, and can be mounted to or dismounted from the washing machine easily.
本發明在對洗滌物進行洗滌時，能夠有傚的過濾洗滌水中含有的異物質，竝且與洗衣機之間的裝卸比較容易的洗衣機的過濾裝置。
ip.com
If any packing materials that may easily produce foreign matters are used to pack the cotton, the Seller shall bear all the expenses for the cleaning of foreign matters.
如果使用容易産生異性纖維的包裝材料包裝棉花，則賣方須承擔全部清理異性纖維的費用。

The Lib Dems are passionate about their pro-Europeanism, their liberal take on crime and their dovishness on military and foreign matters.
ECONOMIST: The new coalition government
Add in the idea that the election will be fought at a time when (for once) voters are concerned about foreign matters in a way that should help the president, and you can see why the Republicans are confident.
ECONOMIST: Party politics
After decades of facing inwards, Indian universities, think-tanks and commentators are only just beginning to show an interest in foreign matters beyond Pakistan, so as yet there is only a small corps of experts outside government to help advise policymakers.
ECONOMIST: India abroad