The searches performed on Monocl, using keywords, refer to the contents of each research activity as a whole. Monocl can also search for techniques and products in the whole publications by searching for the term as free text (click here to see how to use it). However, Monocl also uses the fact that indexed keywords, part of the MeSH keyword hierarchy, are assigned to publications by the National Library in the US as an indication of the field, techniques and contents of the publication. This means that a publication has assigned keywords based on which e.g. diseases, drugs and methods are covered in the full-text publication (as shown in the pictures below).
Thus, even though a specific technique is not mentioned in the title or the abstract, it will often still show up when you search in Monocl, since it has been assigned to the publication by those analyzing the full-text version, including the Materials & Methods section. In the other hand, by using free text searches, Monocl will also check the presence of the term in all parts of the article for the publicly available full-text versions of papers mapped.