Vacume disco.

[Abugarcia]

While working on my suspension this morning I noticed that the vacume disco lines had come off. When I went to put them back on I noticed that there was mud or something on the connection. What's the best way to clean these? Can I blow air in one side and have it come out the other? Do they disconnect with vacume, or connect? I really don't know much about how they work so any info it appreciated.
Thanks