masterjiraya -3 Junior Poster

I have MS EXCEL 2k3
problem:
On my previous post I have the NOT the INTERSECTION of 2 sets of data using VLOOKUP() where is the equivalent function of INTERSECTION in Discrete Mathematics. Right now I was looking for forums if Excel has the ability to combine 2 sets of data not by concatination. In Database Programming the sets of data from multiple tables is possible by using UNION() others are possible also on JOIN().
Since in database programming was possible because I am more excellent in web programming than using excel and finding the possiblities if ever Excel has the ability of computing discrete mathematical operations such as UNION and Intersect.

Scenario:
I have Line A containing a, b, and c (comma mark are separated in cells vertically) Line B has d and e only. what I want in Line C should be the union of A and B in this manner (a, b, c, d and e).
In some forums they are using vlookup in which, as for me, it is unapplicable at some point, because vlookup must have an a common data between 2 sets of data to perform this.

I want to look like this
Sets:

A={a, b, c}
B={d, e}
C= A union B

therefore C should be values of {a, b, c, d, e} (comma mark are separated in cells vertically)