The
薄 in
薄片 is read báo (thin), not bó.
薄 has two readings: báo for the everyday concrete sense ("thin paper," "thin slice") and bó for abstract/literary compounds (
薄弱 bóruò "weak/feeble,"
薄情 bóqíng "fickle"). CC-CEDICT also notes the Taiwan pronunciation [bo2 pian4].
