is there a function ,which

[SoulFly]

searches for a word in some string for example i want to know if the $mystr contains the word hello???????

[barand]

Take a look at [man]strpos[/man] and other string functions

[Krakken]

if (strpos($mystr, 'hello') != false) {
  is there;
} else {
  is not there;
}