This wonderful feature has been recently brought back to life after the great changes in the user interface. Now you can search tasks and folders by the words that are contained in their titles. The filter works really fast (and we work on the performance of the other parts of the system). The temporary folder is created automatically for your search results.
While working with the filtered tasks (by the status, the responsible and/or the due date) and changing tasks they may become colored in gray. This means that after the changes have been made, this task doesn't meet the parameters of filtering.
I really recommend that you to try the search function to harness Wrike's potential.