Re: Relate multiple Maintenace Contract with CI's in SD 5.1
'fraid not - the OOB setup has a single reference from CI to Maint. Contract.
Perhaps when SD 5.1 catches up with 4.5 (Infinite Custom Fields) you can add some more but never a "set" of values.
The best I can suggest at this time is that you create some "child CI" records beneath the original parent - these could carry all of the Maintenance Contracts? Of course this may make a nonsense of your DB design!