A snippet is a small excerpt of the text taken from the relevant page for a particular request. As a rule, and Yandex and Google use their algorithms to automatically generate code snippets for each page.
How attractive is snippet depends for its CTR and position of the site. Therefore, if there is a possibility, should influence this factor in every way possible. For example, prescribe the title keyword correctly generate a description of the page.
But this will work in the case of SARS, but all Use a little differently. In particular, Yandex has no Description, and a piece of the text itself, and predict how it will look like this snippet is practically impossible.
However, always try to create so-called "selling" the titles and texts, using keywords. Query size is 240 characters from Yandex and Google – 160. It should also be taken into account.
In snippete there was no superfluous information back such as "search" button, as well as the dates and additional texts in noindex.
