Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ex-piscor, ātus, 1, v. dep. a. (lit., to fish out; hence, trop.), to search out, find out (perh. only vulg.; syn.: rimor, perscrutor, scrutor, indago, investigo, quaero): proinde expiscare, quasi non nosses, Ter. Phorm. 2, 3, 35: nescis me ab illo omnia expiscatum? Cic. Fam. 9, 19, 1: simul atque audivit, a philosopho voluptatem tantopere laudari, nihil expiscatus est, he asked, inquired no further, id. Pis. 28, 69.