It is for all pages including home and Yes, I have activate the "Use Apache mod_rewrite".any suggestions

Hola, greetings from Spain, I have a problem to configure JoomSEF, when a keyword search on google at the entrance to my web site some are good, www.midominio.com / page.html, but other entries are listed as www .midominio.com / index.php / page.html, and if you click on this link, my page load without the css. How can I fix it?, Thank you very much