This article about reading PDF files in PHP may help, you can start basically by the code provided there and improve it to be able to search using String

https://webcheatsheet.com/php/reading_clean_text_from_pdf.php

Maytham Alabbas

There are many PHP libraries you can go with in order to read and extract content of pdf files.

As of your requirements are for text strings, I would recommend the use of the library "PDF Parser" which is more modern and with ease of use.

You can find it here https://www.pdfparser.org/documentation

Let me know if you find it useful, or even if you find something better.

Hello Maytham Alabbas

I personaly use this library (https://en.wikipedia.org/wiki/Pdftotext) to extract text from PDF with PHP and than make what do you want with text.

In attachment a sample script show how to use it.