Using gems in .rb file

[sunilkumarnagoore]

Hi
i am using some gems which are working in rails but when i make use of gems in .rb file i am getting the below error after installling gem also

in `require’: cannot load such file – daru (LoadError)

please help me about this,
example gem : require ‘daru’

[Asimov]

try require_relative

https://exceptionshub.com/what-is-the-difference-between-require_relative-and-require-in-ruby.html