Collocations for puzzled - adj.

be, feel, look, seem, sound
become, get
We were becoming more and more puzzled by the minute.
I was beginning to get a little puzzled.

remain

extremely, fairly, very, etc.
a little, slightly, etc.
faintly
completely (AmE)
genuinely
clearly, obviously

about
You look very puzzled about something.

at
I was somewhat puzzled at his unwillingness to help.

by
Mrs Sykes seemed slightly puzzled by this.

Puzzled is used with these nouns:
expression, frown, glance, look