* "PI" as in "pie"
* "PH" as in "phone"
* "F" as in "enough"
* "GH" as in "laugh"
So, to give you a good list, I need to know which spelling you're interested in.
Please clarify if you're looking for words with:
1. The "PI" spelling: Like "pie", "pile", "pilot"
2. The "PH" spelling: Like "phone", "photo", "phrase"
3. The "F" spelling: Like "enough", "cough", "laugh"
4. The "GH" spelling: Like "laugh", "tough", "rough"
Once you let me know, I can give you a list of words with that specific sound!