DocumentCollection<TechProductDocument> documentCollection; // from DI
var rersult = documentCollection
.Select()
.LocalParameter("MyLocalParameter", q => q.Categories, query => query.EqualsTo("some category"))
.Execute();
Option 2
Using plain value
DocumentCollection<TechProductDocument> documentCollection; // from DI
var rersult = documentCollection
.Select()
.LocalParameter("MyLocalParameter", "some value")
.Execute();