I believe the Czech here is a general statement. If a statement with 'the' in it were meant, then the Czech would have added the appropriate demonstrative adjective.
So the solution is not to wrongly accept a translation with 'the' here, but rather to correct the previous sentence you refer to, if it is in fact wrong.
There are two different types of adjectives in Czech.
'Hard' adjectives end with -ý (masc sing nom). Those adjectives have different plural nominative endings according to gender: -í for masc animate, -é for masc inanimate and fem, -á for neuter.
'Soft' adjectives end with -í and they have only one plural nominative ending -í, regardless of gender.