This article explains how to use advanced search to filter Jira issues based on values on Multi Project Customfield
Instructions
To build an advanced search
Click on Issues on the top navbar, then click Search for Issues
Click on advanced
Write the customfield name and follow it by space
User is able to pick from the following operators ( is , in , = )
An autocomplete drop-down shall show up with your projects
You may use in your JQL the following advanced functions:
Basic JQL search will be available in the upcoming release.
Basic JQL search will be available in the upcoming release.