Perhaps you should try some spelling variations:
multiling » multilingue, multilingues
multilinguismo » multilingueuismo, multilinguesuismo, multilingualism, multilingumismo, multilingusismo, multilinguistmo
{uml}ismo." » {uml}mismo.", {uml}sismo.", {uml}istmo."
{uml}sismos." » {uml}smismos.", {uml}ssismos.", {uml}sistmos.", {uml}mismos."
{uml}sistmo." » {uml}sismo.", {uml}istmo.", {uml}sisto."

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

• If you are trying to use Boolean operators, they must be ALL CAPS: "(multiling or multilinguismo)({uml}ismo." OR ({uml}sistmo." or {uml}sismos."))~.
• Removing quotes may allow a broader search: (multiling or multilinguismo)({uml}ismo. or ({uml}sistmo. or {uml}sismos. ))~.
• Adding a wildcard symbol may retrieve word variants: "(multiling or multilinguismo)({uml}ismo." or ({uml}sistmo." or {uml}sismos."))*.