search for a string containing special characters within a STD::string ( c++ )

Heya

I got a long string from a HTML request. I need to find the following substring within:

<&randomtag>

However when I'm trying to search it gives me wrong results.

If I replace the string with something, not containing "<" ">" it works flawlessly.

Relevant code:
(not copied, might have some typos, but works without special characters)

std::string readBuffer; //longlongstring
std::string starttag;
std::string endtag;

size_t sstart;
size_t send;

//...................

sstart=readBuffer.find(starttag);
send=redBuffer.find(endtag);

correction=readBuffer.substr(sstart,send-sstart);

std::cout << correction << std::endl;

So yeah, if anyone happens to know a way to fix this, I'd very much be greatful :)
Thanks in advance

Tags: C++, C, String