Is there any way to tell nicehash to mine a specific coin or no?

Just reading some comments here it seems like some of you can point it to certain coins?
Of course. Point your rig to nicehash using the following format:
stratum+tcp://[algorithm].[region].nicehash.com:[port]
You'll have to fill in the blanks for the algorithm, region, and port.
For instance, if you wanted to mine X13 to the USA servers you would use:
stratum+tcp://x13.usa.nicehash.com:3337