[AccessD] Separate selected records from a table

Hi again :)
in a table there are names and in some cases there are two names with a "," 
between them
What I want to do is to separate only the records keeping the second name.

I tried the follown
1st: Right$([director];Len([director])-InStr(1;[director];","))
2nd: Left$([director];InStr(1;[director];",")-1)

but it returns with 2 problems
1. in 2nd (Left$) #ERROR for the blank records
2. in 1st (Right$) a space " " in the begginning of the separated records

thank's
/kostas