English as foreign language (EFL) learners in general and Vietnamese EFL learners in particular might find that writing is a task of challenge, even advanced EFL learners who have good competence in grammatical structures and lexical resources might struggle in producing coherent writing that meets native English speakers’ expectation. Observing the coherenre problems that Vietnamese EFL learners have encountered, I collect a number of their academic essays, specifically argumentative writing to analyze theme and thematic progression (TP) patterns, which is recognized as one of ways to analyze textual features to identify how themes unfold the text. Specifically, this study examines theme choices and TP patterns used in argumentative writings by Vietnamese EFL learners and by American professional writers to see the differences in usage of themes and TP patterns between two groups. To identify these differences, both qualitative and quantitative methods are used in this study. These differences can be attributed to several factors, including rhetorical conventions, overuse of cohesive devices, translation from first language (L1), as well as side effects of second language (L2) training. These factors might make learners’ writing incoherent, less convincing, and hard to follow. To help Vietnamese EFL learners recognize these factors and improve coherence in their writing, a training course on theme and TP patterns is developed. This course might provide basic theories about themes and TP patterns, and guide EFL learners to make the theme choices and use TP patterns to create smooth flow of ideas to achieve success in their English writing.