ga:- - prepronominal prefix - when used with an infinitive, it means "the ability" to perform the action of the verb.
See Montgomery-Anderson "Cherokee Reference Grammar", p. 298-299
u- - "s/he", this is a "B" Class bound pronoun, used before a consonant.
-nvsi- - verb root of "move, crawl around"
-dasdi - infinitive suffix.
This particular verb isn't documented in vetted dictionaries but is clearly a form of ᎠᏓᏅᏏᏂᏙᎭ minus the "ada-" reflexive prefix.