Debugging a thread

I am working on target which uses threads (4 in number) to check for a presense of dongle. I am also using ollydebug to work on this target. How can i work with this. I was put off by a statement in Hacker Disassembly Uncovered which states

" In general, threads are great things that demand a special approach. It is difficult for a human to recognize that a program can run simultaneously in several places. Commonly used debuggers have a weak point: They debug each thread separately, never simultaneously. The following example shows how this can be used for protection."

Is there a way to override this ? How can you debug threads.