"I looked for a person that can repair the telephone."
Translation:ghogh HablI' tI'laHbogh ghot'e' vInej.
The -'e' indicates that you are looking for person that can repair a telephone (ghogh HablI' tI'laHbogh ghot'e'), rather than a telephone that a person can repair (ghogh HablI''e' tI'laHbogh ghot).
Without the -'e', ghogh HablI' tI'laHbogh ghot would be ambiguous between the two meanings.
English "fronts" the head noun. In other words, English moves the noun that the relative clause describes to the front: " a person that can repair a telephone" as opposed to "a telephone that a person can repair" - either way, "a person can repair a telephone", you just have to figure out whether you are looking for that person or that telephone.
Klingon maintains the OVS structure for the clause and instead has an option to mark the head noun with -'e' to make it clear which noun is the head noun. The nice thing is that you don't have to mark the head noun in Klingon. You can leave it ambiguous for poetic reasons, or because both interpretations are true and you want to just say it in one sentence, or whatever reason. You can't do that in English, you have to pick a head noun to front.