put out feelers
Discreetly try to learn something, as in They put out feelers to see if anyone was interested in buying the company. This idiom alludes to an animal's feelers, such as antennae or tentacles, used to find food. [First half of 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.