hey, i am using hamming distance for matching fingerprint images.but it is not matching at all. please help me and tell me what should i do??..should i use euclidean distance instead of hamming distance??if yes how??

i have a database of 200 feature vectors. Everytime i rum my query vector to match with database it always gives incorrect results and matching percentage is also very less like 5 or 7%..what should i do so that i get correct results??