Hi Laura - you can add both of these triggers to one smart campaign. You don't been the "OR" logic filter because triggers automatically work that way. If you add both triggers to one smart campaign, you will be good to go because a person will go through the flow if any are activated.
You can read more here: Define Smart List for Smart Campaign | Trigger - Marketo Docs - Product Docs
Scott is right. Many of our nurture programs use multiple triggers in the smart campaign. "Data value changes" or "campaign is requested" or "lead is created" are common ones used concurrently. The smart campaign is listening for any of those triggers. The boolean logic is only for filters.