How to prevent the results from being truncated?
You can simply add a new view mode for search results:


Go to admin/structure/types/manage/page/display (where "page" is your content type)
Expand the Show Custom display settings fieldset
Check Search index





Click Save
Go to admin/structure/types/manage/page/display/search_index (again, where "page" is your content type)


My advice would be to use download the Display Suite module (and enable the Display Suite module and Display Suite UI module) for extra fields and more options. No custom theming or coding required!