1. A method for providing keyword ranking using a common affix, the method comprising: providing a keyword set that comprises keywords input to an Internet search environment as search queries; counting, in the keyword set, keywords that comprise affixes with a common attribute; calculating a ranking of each affix using the counting result of the keywords and extracting a common affix, the calculating including applying a weight to the counting result of the keywords based on an attribute of each affix, the weight according to the attribute of each affix increases as query counts of each affix being a keyword itself increases; and establishing a regular expression comprising the extracted common affix and a search combination symbol.