"钢琴演奏技巧" can be translated into English as "piano playing techniques" or "piano performance skills".
"Piano playing techniques" emphasizes the technical aspects and methods involved in playing the piano.
"Piano performance skills" focuses more on the overall ability and proficiency in performing on the piano, which includes not only technical skills but also musical expression and interpretation.
Both expressions are commonly used and can be chosen based on the specific context or emphasis.