I am having a hard time understanding your question, but will try to answer anyway.
In case of an salt like NaNO2 you have to know the cation and anion of the salt; in this case Na+ and NO2-. Those common ions you just have to learn. So this salt would be sodium nitrite.
As for acids, you just have to learn them. I cannot name an easy reminder aside from looking at the distinctive element.
For example: HNO2 is called nitrous acid. (nitric acid is used for HNO3), Sulfiric acid for H2SO4, Hydrochloric acid for HCl, Perchloric acid for HClO4, Phosphoric acid for H3PO4 and Hydrofluoric acid for HF.