1. Nén file PDF
https://www.compress2go.com/ (miễn phí)

2. PDF to Excel free

https://thebestpdf.com/

https://www.ilovepdf.com/

https://smallpdf.com/

3. Clone website

https://saveweb2zip.com/en

4. Gỡ lỗi chia sẻ facebook

https://developers.facebook.com/tools/debug/

5. Gỡ lỗi chia sẻ zalo

https://developers.zalo.me/tools/debug-sharing