Data is only useful if you can get your hands on it. When you have mountains of data to wade through, you need the best, most efficient methods of finding precisely what you are looking for. The easiest way to look for a needle in a haystack is to use a magnet. A good search strategy is that kind of magnet, helping you find that needle of desired data in the haystack of countless sets!
Classical metadata schemes might not be sufficient to guide one to all relevant data sets. The name of the data creator or the year of publication might not be known. Many times data sets are linked to research papers but this does not simplify the search because research papers are just another haystack. A combination of keywords or title words are rarely unique and may yield numerous hits.
Using classical metadata and viewing long query result lists is time-consuming, but even with this method there is a risk of not spotting relevant data. Either one does not know the best keywords or the creator did not label the data set with the best keywords. This presentation makes suggestions on how to find geoscientific data better and gives examples of web based information systems.