Dear Alan
If u use the following formula

=VLOOKUP(LEFT(A2,SEARCH(" ",A2)-1),Source!A$2:B$45,2)&" "&VLOOKUP(REPLACE(Data!A2,1,SEARCH(" ",Data!A2),""),Source!A$2:B$45,2)

on the sample file , the result will be ( R5 S2), that is the first & second Name in A2 Cell in data sheet, you can try it yourself.
so i believe their is a way to do it, I need the result to be ( R5 S2 R6 M2). thanks