The reason for this is these symbols (apostrophe, punctuation mark, sometimes called a diacritical mark and double quotes, quotation marks, speech marks, inverted commas) can cause problems with downloading correctly in the system.
So the symbols ' and " will be replaced with the ` symbol (grave accent). This symbol does not cause any issues so will be used instead. However if you do a title search with the ' or " the system is designed to still find the SKU, it will just be displayed on screen with the grave accent symbol instead.
Commas (,) will also be simply removed as they can also cause issues with Imports/Exports. So if you have any commas in the titles, they will be removed. So if you are searching via the title search you will need to search without the comma so the system can find the SKU.