About usage of the special Polish letters: ą ć ę ł ń ó ś ż ź

about ą ć ę ł ń ó ś ż ź
when do I use them? cos I have problem finding the associated english word in dictionary when one of those appears in a polish word:-(

for example: 'zwrotow'

'zwrotow'

you can't find this one ('zwrotów'), because it's not in it's basic form (singular, first case - denominator), it is 'zwrot' you should be looking for in this case

it's not the presence of those letters, that makes it hard to find a word in a dictionary