Anna and Tania went shopping but _______ couldn't find anything _________ liked.
Explanation
Anna and Tania went shopping but they couldn't find anything they liked. انا اور تانیہ خریداری کرنے گئے تھے لیکن انہیں اپنی پسند کی کوئی چیز نہیں مل سکی۔The pronoun "they" is used as the subject referring to both Anna and Tania.The second "they" is also correct as it refers back to the subject.It indicating neither found anything they liked.