If I understood you correctly (w/ a grain of salt, lol) you may be able to use...

=IF(VLOOKUP(x,xx,x,x)=0,"",VLOOKUP(x,xx,x,x))

Or if you download install the morefunc.xll addin, a great tool, you can make use of other functions and use this - much more efficient...

=IF(SETV(VLOOKUP(x,xx,x,x))=0,"",GETV())