Treating "f" and "ph" equally (without typos)

Hello together,

I am using algolia successfully for my products but there is one thing I have trouble implementing.

Forgive me this question but googling it is a pain, as “f” and “ph” are just letters that can be found in every word :smiley:

So my requirement is quite simple, when free text searching for a word containing a “ph” or “f” these should not be considered typos, therefore rank equally.

Example.

Magnesium Sulphate vs Magnesium Sulfate

I also have similar cases for “i” and “y”

Thanks in advance !