The study focuses on the language learning experiences of adult migrants from refugee backgrounds with limited educational experiences before migration. This group is often referred to as LESLLA learners; LESLLA is an acronym for Literacy Education and Second Language Learning for Adults. The study used Constructivist Grounded Theory (CGT) -- a data-driven, bottom-up methodology for qualitative research -- to gain understanding of the conditions that help or hinder LESLLA learners' language development and of the strategies they use to enhance learning and to overcome obstacles. The dataset is comprised of thirty interviews with adult refugees from Syria and Eritrea learning Dutch in the Netherlands. The analyses identified self-efficacy, which has been described as 'the soul of strategies' (Oxford, 2017), as a core category, differentiating between learners who showed contentment about their language learning achievements and expressed confidence in further learning, and those who expressed little confidence and a sense of failure. Conditions hindering self-efficacy include the cognitive conditions 'forgetting' and 'stress', and the social condition 'isolation'. Facilitative conditions in the cognitive realm are 'motivation' and 'language learning strategies'. 'Social strategies in new social networks' is the condition that stands out as strongly supportive for self-efficacy. The data showed how LESLLA learners are often not in the position of power to build their networks. This means that social strategies are not an individuals' asset but rather a condition that is distributed in a social system.