VLOOKUP to match numbers to strings of text

Hello,

I am trying to transfer numbers from one excel sheet to another excel sheet. The old excel sheet has numbers in one column that correspond to a particular string of text in the column next to it. The new excel sheet I want to transfer these numbers to the same strings of text, but there is a second column with more information making the strings of text appear multiple times.

For example. Excel sheet 1, Column A and B

12345 - Green 2
12346 - Red 3
12347 - Yellow 4
12348 - Blue 1

Excel Sheet 2, Column A and B
Green 2 - A
Green 2 - B
Green 2 - C
Red 3 - A
Red 3 - B
Red 3 - C
Yellow 4 - A
Yellow 4 - B
Yellow 4 - C
Blue 1 - A
Blue 1 - B
Blue 1 - C

So I would want the 123... number to match up with the same color name in sheet two. So in the second sheet all Green 2's would have the 12345 number next to it in a separate column.

I tried to play around with VLOOKUP, but I am not successful so far. Any ideas? I'm willing to do an extra leg of work if this is not easy/doable as is.