The coefficients aren't statistically significant

[vannguyen15]

Hi everyone,
I'm a new Eviews user. My dataset includes 10 countries from 1991 to 2011. When I run OLS, the coefficients for some key variables are statistically insignificant with big p-value. However, in the original paper, those variables are statistically significant. Could you show me how to solve this problem? Thank you very much in advance.