Here’s one way, using the vlookup function. (I imagine it could be done using index & match too but this is the first thing that came to mind.)
First, on the ‘other sheet’ that contains the Product Suppliers, (in this example, Sheet2), insert a new column to the left of the suppliers’ names. (ie., the suppliers become column B with a new blank column A.)
Next, copy the list of Product Codes into the blank column A, (obviously, making sure each code is represented by its proper supplier in the next column.)
Now you can go back to the sheet containing your original list of product codes and (insert a new column to the right of this list if needed) and (say the codes are in column A, starting in row 2), in B2, enter the formula: =VLOOKUP(A2,Sheet2!$A$1:$B$4,2,0)
(In the formula, change the range “A1:B4” to the real range your data in sheet2 occupies.)
Then you can copy this formula down as far as your product codes go.
You can then delete the Sheet1 column A (product codes) if you like, just remember to Copy & PasteSpecial (as Values) the formulas in column B first.
As usual, work getting in the way of fun (and a timely response).