Although there are some words of Portuguese origin in Haitian Creole, like kachimbo 'earthenware pipe', there is no save word meaning 'know'. 'Know' is expressed by another word, konnen (< connaître).
Sa (< savoir) exists as an attenuated alternative of the modal kapab 'be able to'. The Atlas linguistique d'Haïti (Fattier 1998: 876-877) lists two meanings of sa:
1) epistemic:
mwen vini pou m sa palé avè w
1SG come PREP 1SG MOD talk PREP 2SG
'I have come in order to talk to you.'
2) deontic:
li pèd pawòl, li pa sa palé
3SG lose word, 3SG NEG MOD speak
'He has lost his voice, he can't speak.'