I would like to join text from different cells into one cell. This is for Google sheets. I tried concatenate and join. But they don't seem to work. I realize that it can be done using the & function but it would bea drawn out equation since I have multiple multiple cells to join.

Sample spreadsheet. ..

A B
1 john 2321
2 Cindy 5543
3 Bob 4665
4 Mike 5543
5 Sean 4356
6 Vince 5543
7 Walter 6667

I would like to know the formula to combine all the instances of 5543 into one cell. For eg. The outcome would be VinceMikeCindy