Integrating corpus consultation to help students' re-use of vocabulary items for essay-drafting has not been sufficiently examined in instructional contexts. This chapter investigated the linguistic features of target words for which students consulted concordance programs to include in essays by documenting the DDL of three groups of EFL students in a Taiwanese college writing program. Participant essays, video files of consultation processes, responses to questionnaires, interviews, and written records of corpus consultation were examined. Researchers found 88.14% of all consulted words were incorporated into essays, with learners looking up 3.18 words. The lexical profile of consulted words indicates that learners mainly used the most common 1,000 to 2,000 words with more verbs more frequently consulted than nouns. Students queried words for confirmation or incorporated the discovered vocabulary into essays. As emergent pattern hunters, the participants made only limited use of dictionaries and bilingual resources. Implications of the findings are discussed.