SQL & PL/SQL

Hi All

I'm trying to run the code and running into trouble

CREATE OR REPLACE PROCEDURE TEST (
P_USER IN VARCHAR2,
P_PLANT_ID OUT VARCHAR2
)
IS
vUser VARCHAR2 (10) := P_USER; -->> P_USER can be any thing like YAHOO,INDIA,LANDON
BEGIN
vUser := SUBSTR (vUser, 1, INSTR (vUser, '''', 2));


INSTR (vUser, '''', 2) -- > this part is creating problem, its returning 0 only, not sure what is '''' in INSTR (vUser, '''', 2).

can anyone please help to to reframe the INSTR (vUser, '''', 2), so that it will return proper value, Like for YAHOO it must be 5, LANDON - 6, just don't want to use LENGTH function.

thanks is advance for help.