为讨个吉利我就喝一杯。

I'll take just a cup for luck.

《新英汉大辞典》

我只是想为自己讨个公道，同时也为面临同样问题的人讨个公道。

I just wanted to find some justice for me and for others facing the same problem.

youdao

若你这个桃花仙子有知，会不会娥眉横竖，为自己讨个说法？

If you have to know that Peace to all, will crescent anyway, for his discussion of argument?

youdao