Perhaps you should try some spelling variations:
multilingues » multilinguismo
multilingueues » multiligues
{uml}uismo." » {uml}mismo.", {uml}iismo.", {uml}uisme.", {uml}umismo.", {uml}uistmo.", {uml}uiso."
{uml}sismo." » {uml}sismos.", {uml}mismo.", {uml}simo.", {uml}smismo.", {uml}sistmo.", {uml}siso."
{uml}ismo." » {uml}mismo.", {uml}istmo.", {uml}iso."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: "((multilingues or multilingue) or multilingueues)(({uml}uismo." or {uml}sismo.") or {uml}ismo.")~.
• If you are trying to use Boolean operators, they must be ALL CAPS: "((multilingues or multilingue) or multilingueues)(({uml}uismo." OR {uml}sismo.") or {uml}ismo.")*.
• Removing quotes may allow a broader search: ((multilingues or multilingue) or multilingueues)(({uml}uismo. or {uml}sismo. ) or {uml}ismo. )*.