Query: Find Duplicates not identically

I have a table that includes supplier invoice
MyTable (Col1, Col2, Col3)
MyTable (Col1, Col2, Col3)
Col1 Col2 Col3
1 001 F2015/5
2 002 FAC78
3 001 F2015/9
4 001 F/2015/05
5 002 F456

Looking at my table for the same founisseur (Col2) almost the same code(Col3) which may be the same, the risk that the user enters the invoice 2 times by changing a character

As the case of Line 1 and Line 4