Will my previous credit score be considered if I stayed there for few years and going back again?

Your credit profile usually doesn't stay active for more than 6 months. From next time, call the credit card companies and let them know that you'd be using the card abroad.
However, since your card profile has become inactive, you'll have to add positive items in your credit report. A creditor/lender may not agree to approve your loan request. And, as you did initially, request everyone to report your financial transactions to the credit bureaus. If you're not getting anything, take out one secured card and manage it efficiently. You can also take out a credit-builder loan. Your credit file will become active gradually.

You can't get a new mobile connection with your previous credit score simply because it's not valid anymore. You have to start afresh. Understand this fact very well. At the most, you can show your past credit report, but I don't think that would be approved.

You need to build credit score again. Get a card, and manage well to rebuild your credit health again.