Drop down list possibilities

[HH&Excel]

I have a table with two headers, ABV. and Emails, on sheet two. On Sheet one I wish to create a drop down list to select multiple items from the table and input them into one cell. I have tried data validation, but the size of font was too small. I read through previous forums and referenced "http://www.contextures.com/xlDataVal08.html#Font" But couldn't find exactly what I was looking for. The data validation combo box would be perfect, if I could input more than one selection from the previous table. Thanks ahead of time!