Flattery, blarney (4,4)
I believe the answer is:
soft soap
I believe this is a double definition.
'flattery' is the first definition.
(soft soap is a kind of flattery)
'blarney' is the second definition.
(I know that soft-soap is a more specific form of the action blarney)
(Other definitions for soft soap that I've seen before include "Use flattery on (someone)" , "(Use) flattering talk" , "Flannel" , "Flattering talk from tender cleanser?" , "Flattery of cleansing kind?" .)