Hello H, I assume that you have 4 years of experience in your computers business. Primarily it is important to understand was it totally hardware, software, or both. Moreover when you say you have a little bit of knowledge of everything, every platform and every technology, then probably you have to assess your knowledge and interest that in these 4 years which is the field or technology/area you gained better knowledge than other areas/ technologies of IT. This itself will answer your question about which stream you should excel your knowledge to get a job in a company. Best way is to look at some of your satisfied customers to whom you provided solutions and try getting a job at one of those places to start your career afresh. From thereon you can sail your boat further smoothly.