A search consultant is essentially simply a type of recruitment agency employee. They get paid to place you in jobs for other companies, and often take a cut of your first years salary as a reward.
This means that they should only put you forward for jobs that they think you have a chance of getting as they will only get paid on results and the company will expect to receive some good quality candidates for its roles.
Search consultants often have specialist knowledge of a particular field, and this is good for companies as it means they get good candidates, and good for you too as it means you can get placed in front of people with suitable jobs for you.
Note that if you use search consultants, you should hope to get placed quickly. If this doesn't happen they will place less perceived value in you, and therefore market you less. As mentioned they only get paid when you get placed so if you drag on for a while without being placed, as it were, you are less attractive to them.
Therefore if you use a search consultant ensure that you vet roles they suggest you apply for. Only pick roles that you think you have a real chance of getting.
You know yourself better than the search consultant at the end of the day so if you don't think a job is suitable, simply bat it back to them. That way you haven't wasted your time, the search consultants or the company.
By being selective with the roles from the search consultant that you take to interview you increase your chance of finding a job you have a great chance of getting the right job for you.
Note therefore you should try to get a face to face meeting with a search consultant to tell them what you want and not rely on them matching just from your CV. If they are not prepared to meet you then they are not worth your time and look for another search consultant that will spend a little time finding out what you want.