particularizers
Particularizers are a category of adverbs that focus attention on what follows them, without excluding other possibilities. They are used to modify verbs and adjectives and can be found at different levels of English Vocabulary Profile such as A2, B1, B2, C1 and C2.
The TED corpus has some examples of particularizers used in natural chunks. For example, “especially when it comes” is a 4-gram chunk that is at least C1 level. “Largely due to” is another 3-gram chunk that is at least C1 level. “Mainly because” is a 2-gram chunk that is at least B2 level.