When searching in description you can use the logical Operators AND and OR.
The search "apx AND dualband" whould find Dual-banded APX-Antennas, the search "apx
OR dualband" whould find all APX-Antennas and other periphery which are related
You can also use paranthesis to refine your search.
A search of "apx AND (single OR dual)" whould find all APX-Antennas which are related
to single- or dual-band.