There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
(a)láqainen
adverb. by no means
alla
none, nothing, none, nothing, *no [adj.]
A negative adjective appearing as {(a)láqa >>} alla in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/105 note #67), so probably meaning “✱no” as in alla Elda pole quete “no Elf can say”. It can also be used pronominally to mean “nothing”, and for this function it has a variant lála (PE23/104). For example: merin alla “I want nothing”, or merin alla sino “I want none of this”.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
A correlative combination appearing as {láqainen >>} ᴹQ. (a)láqainen “by no means” in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/111), a combination of ᴹQ. láqa “none” and the instrumental suffix ᴹQ. -nen.
Neo-Quenya: For purposes of Neo-Quenya I would update this to ᴺQ. allanen “by no means” using later ᴹQ. alla “none”, also from DRC.