The strange thing Ms. Lou mentioned wasn't Shu Yu guessing that they were missing a hoe from their home, but rather...
"On the morning after that incident, Ruan Jinqian came running to our house from the village entrance, looking for my father-in-law to act as a judge, saying his hoe had been stolen and wanting my father-in-law to help him find it."
A hoe is a metal farming tool. Although metal tools these days can't compare to gold, silver, or jade, for ordinary farming households, it's still an asset. Losing it like that, of course they wouldn't accept it, especially since the hoe was relatively new.
According to Ruan Jinqian, that evening he went to plow the field. Halfway through, he got tired and placed the hoe on the ridge, went under the shade to drink some water and took a short rest.
In just that while, when he returned to the field, the hoe was gone.
