Full text keyword strings search
For certain technologies, full text keyword string search would be more appropriate. For example, if we lookup for a cell phone with a proximity sensor, we would consider a full text keyword approach first because the term of “proximity sensor” in Japanese is very unique; almost everybody would use the same term to describe this feature. However, because of the high noise of full text keywords, we usually would use either a wide F-term class or wide F-index, or wide IPC class as a filter to reduce the search noise.
Search strings for “proximity sensor” in Japanese:
FK=近接センサー + 接近センサー + 近接感知 + 接近感知 + 近接検出 + 接近検出
If the full text search produces too high a noise, we may lookup claims and abstracts, but usually we do not focus on for titles and abstracts, because we consider such titles and abstracts are too narrow.