Symbol Search in Container
A user adds a "Symbol Container" to an artboard.
The container is a searchable field and the user can do a search (in context) to find the symbol they need.
The search will auto-suggest the Symbol.
And show a thumbnail of the Symbol prior to selection.
The user selects a Symbo, which will 'load' into the container and resizes the container accordingly. The user could also change the Symbol by 'double clicking' the container to retype (with in the same container).
Please also take a look at https://adobexd.uservoice.com/forums/353007/suggestions/17026741