Blog overview page: blog texts are completed with 00000000's

I have this small issue: on my blog overview page, my most recent blogs appear by their image and the first sentences of the blog text. As I have several blogs without text - only images - the text field on this overview page is completed with 0000’s. Is there any way I can get rid of these 0000’s?

Have a look at my blog to understand it better:

Thanks for your replies!