Then, we're getting all these results here, about all the ones that match this substring.

然后，我们在这里得到所有这些结果，关于所有与该子字符串匹配的结果。

Then, in the next line we're running the grep command which is just search for a substring in some file and we're searching for the string foobar in the file.

然后，在下一行中，我们运行 grep 命令，该命令只是在某个文件中搜索子字符串，并且我们在文件中搜索字符串 foobar 。