Hi cecillemaquito,
First of all did you create a child theme while customizing the code? If you have not created a child theme then while updating to new version all your customized code will be lost. So better make a child theme and then customize the code otherwise the same changes you need to do after updating to the theme.
For your question, goto theme folder -> library -> structure -> header-extension.php on line no 322 you will find this code
__( 'Google Plus', 'attitude' ),
replace this code with __( 'Google scholar', 'attitude' ),
Hope this may help you
Thank you!