扑空

扑空	pū kōng	lit. to rush at thin air / fig. to miss one's aim / to have nothing to show for one's troubles
扑	pū	to throw oneself at / to pounce on / to devote one's energies / to flap / to flutter / to dab / to pat / to bend over
空	kōng	empty / air / sky / in vain
空	kòng	to empty / vacant / unoccupied / space / leisure / free time