Yes, you can easily do this from the Projects List screen. You need to first select 2 or more projects to merge following instructions below.
1) Use "Ctrl + A" to select all projects, or "Ctrl + Mouse" to select individual projects, and "Shift + Mouse" to select projects that are grouped next to each other.
2) When the projects have been selected, right mouse click and select the option “Merge into New Project”
This will create a new project called "Merged Project" with all the items combined from the selected projects.