Salary difference

Question

i have been to many interviews..i am confident that i can make it after interview regarding my experience as Developer or i can say Multi sikills since i did Web development and Maintenance, Software testing, Documentation all of this but i got less pay..Since i have looking for jobs in other big IT company i fell bad that through my interview i figure that my salary from my current jobs make the difference..Please i need your advice whta should i say to those Managers who interviewed me on this type of question...I know that it surprise them wat i did and what i was paid for..thanks