I have large TXT files in arabic Tashkil and I'm trying to find lines that contain specific pattern mashkula with َ ً ُ ٌ ّ ْ ٍ , I've tried the following grep syntax:

cat file.txt | grep "اهلا"

This returns nothing until I insert Tashkil marks:

cat file.txt | grep "أهْلاً"

I get the correct output

أهْلاً

I also tried

grep -P "[ُ ّ َ ً ِ ٍ ٌ ْ ~]|[اهلا]" file.txt

And this returns all matching characters in different patterns:

أهْلاً أ ... هْ.. لًا أنْتَ لَيْلاً ..

How to match arabic diacritical marks with grep?
Is it possible to remove Tashkil marks from text before using grep?
My OS is Ubuntu 18.04

UPDATE: At this moment, I remove Tashkil marks from text with:
sed "s/[ُ ّ َ ً ِ ٍ ٌ ْ]//g", then I can grep what I want. But in this approach, sed command removes spaces from all text!