This is an ordinary Google search feature which is sometimes handy to see how a particular customer uses certain terms.
1. Enter the German term that you are looking for.
2. Enter the address (URL) of the (customer's) web site where you would like to search.
3. Click on search to see the Google search results.
Open the one that looks promising and you will find German text which helps you to understand what they are talking about. Sometimes, if you find DE in the address shown by your browser and replace it with EN, you may find an English translation.
4. For your next search, just change the term.