Herramienta de investigación muy simple en APEX

I am trying to do a very simple "Research" tool in Apex.

What i did so far is

1. Created a textbox
2. Created a button with the attribute /Always submit page when enter pressed/
3. Wrote this query in the report page - Source - Source region

-

"select NO, TITRE_CONFER, NO_CONFCIER, NO_FILM FROM S4_CON_VRAI
where titre_confer like '%' || :px_2 || '%'"

This is pretty much a table with conferences that are either taught with a film or a person. I am looking to filter the TITLE of the conference. px_2 is my textfield. So, if you enter any letter, it should filter with the right title. The problem is that whenever i click GO, nothing happens. He still shows me the whole list.