Nowadays, vocabulary learning plays an important role in language teaching especially in the context where English is taught as a foreign language. This is because lexical competence is now seen as the heart of language learning and the ultimate goal of language teaching is to improve the language competence of learners. Additionally, vocabulary has been recognized as an important factor for language learning because insufficient vocabulary knowledge leads the learners to encounter difficulties in language learning. Learners can significantly improve their language competence by developing their ability to use vocabulary learning strategies (VLSs). The present study primarily aimed at investigating how Thai university students deal with vocabulary problems. The participants were 63 undergraduate students studying at Khon Kaen University. A semi-structured interview was used as a method of data collection. After completing the stage of data collection, the interview recordings were transcribed verbatim and then translated from Thai into English for the purpose of data analysis. The translated data was then validated and analyzed. Under the constraint of language learning, the results show two main purposes in employing strategies for dealing with vocabulary learning problems: 1) to discover the meaning of unknown words; and 2) to retain the newly learned words in long-term memory and recall them at will. Furthermore, the data indicated that there are three groups of strategies employed for discovering the meaning of new words, i.e. Discovery, Social,