Change post length showing on Yanews

Hi. I have installed Yanews and like the template but the posts are only showing about four lines. How do I change it so that I can have them either full post or add my own page break where I want it(read more etc). Some of the posts are short and I want the whole post showing.

I dont know where (in the stylesheet?) to change it, hence can anyone please help? ??

website: https://aurorasunrise.com.au

Thanks.