માંખણમાંથી મેવાળા ખેંચે તેવા ઝીણા છે.

māṁkhaṇamāṁthī mēvāḷā khēṁcē tēvā jhīṇā chē.

Literally: They are so sharp that they pull a hair out of butter.
What it means: Said of an extremely cunning, precise, or stingy person who can extract profit or find flaws in the smoothest situations.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1923) ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1921) · read from the scan by machine — the Gujarati itself is unchecked · English is machine-made and nobody has checked it yet

Heard it differently, or know we've got the sense wrong? Tell us — that is exactly the kind of correction this needs.