Searching for “searching”
The Maharsha questions the choice of the verse, noting that another option has the dual advantage of being earlier in the Chumash and also having “finding” in a negative context: Bereishit 31:33, “And Lavan went into Ya’akov's tent, and into Leah's tent, and into the tent of the two maid-servants; but he found them not.” The Maharsha offers two possible explanations.
Rav Pinchas Hirschprung (as quoted by R. Tevel Hirschprung) noted that the later verse is actually more appropriate for bedikat chametz the way it is practiced. The notion of placing crumbs around the house to be found is an unusual way to look for something, in that it has been intentionally planted so that it can be “discovered”. However, we do find such a “finding” in the Torah – the goblet that had been intentionally planted in Binyamin’s sack. Thus, this verse is uniquely fit for the Talmud’s citation.