Understanding plural/singular nouns is way beyond the plugins capabilities. It would require a very sophisticated dictionary as well as understanding all singular/plural rules of each language, and a very powerful server to process this information.
There are a few compact solutions, but unfortunately none of them work properly, not even for english language.
The plugin simply matches the keywords given to the fields chosen by executing a database query. Perhaps the easiest solution in this case are:
– Using the additional keywords field, that allows asigning more search keywords
– Using a custom code to replace search phrases with others: Knowledge base – Replacing search keywords
The first solution is neat for cases where there is only a handful of products that you want to assign custom keywords to. The second solution is more generic, as it replaced wth words within the search phrase directly – for example you can assign the keyword 'glasses' to be replaced simply by 'glass'.Best,
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