I/you can't/couldn't ask for a better something (also I/you can’t/couldn’t ask for more) used to say that you are very happy with what you have or with a situation 我/你不能要求有更好的(某事物)了〔表示对所拥有的或某状况非常满意〕 I couldn’t ask for a better boss. 我不能要求有更好的老板了。
→ I/you can’t/couldn’t ask for a better something at ask1(1)