php error

Hi, i have a page with {exp:channel:entries}…{/exp:channel:entries} tag first and below an {exp:search:search_results }… {/exp:search:search_results} tag

I get some php error and I don’t now hot to resolve this issue

A PHP ERROR WAS ENCOUNTERED

Severity: Notice

Message: Undefined index: search_excerpt

Filename: search/mod.search.php

Line Number: 1439

A PHP ERROR WAS ENCOUNTERED

Severity: Notice

Message: Undefined index: search_results_url

Filename: search/mod.search.php

Line Number: 1475

A PHP ERROR WAS ENCOUNTERED

Severity: Warning

Message: Cannot modify header information - headers already sent by (output started at /home/dellanet/public_html/sir/system/codeigniter/system/core/Exceptions.php:170)

Filename: core/Common.php

Line Number: 475 Please, some help Thank you very much

Michele