I don’t have the “log” language to which you refer… but many of the language lexers allow for adding custom keywords to existing styles. For example, Settings > Style Configurator, Language = LISP, select Style = FUNCTION WORD and you can add other custom keywords to the User-defined keywords box. It may be that your “log” language has similar – so if “log” shows up in the Language selection column, then look through it’s various Style column items, and see which ones have customizeable boxes. Any that do, you should be able to add keywords into those styles.
That description assumes the “log” language is above the vertical bar (ie, above “Define your language…”) in the Language pulldown. If the “log” language is below the “Define your language…”, then it’s a User Defined Language (UDL), and the methodology will be different.
Go to Language > Define your language..., then in the User language pulldown, select “log”. Go to the “Keywords List” tab, and either add your keywords to the existing styles, or if some of your 8 groups are empty, you can create new group(s) with unique style(s) in any empty groups. Ivan Radić has made available documentation on how to use UDL v2.1.