I haven't used it for a long time, but it seems that if you search a phrase with a plural word, you only get results in singular form. For example, here's the results for the phrase "cell phones" (without the quotes):
Searches done in October 2004
Count Search Term
2108744 cell phone
116054 cell phone plan
47332 at t cellular phone
16617 cellular phone family plan
11397 nokia cellular phone
11011 international cellular phone
6939 cellular phone ringtone
6431 cellular phone company
6359 lg cellular phone
6119 samsung cellular phone
5900 sprint cellular phone
5822 cellular phone wallpaper
5404 verizon cellular phone
5306 gsm cellular phone
4971 cellular phone deal
4698 free cellular phone ringtone
4387 cellular phone numbers
3903 cellular phone directory
3635 cellular phone battery
3549 cellular phone rental
3404 us cellular phone
3252 nextel cellular phone
3184 free cellular phone wallpaper
3110 cellular phone faceplates
3036 cellular phone review
2907 cheap cellular phone
2789 cellular phone services
2760 cricket cellular phone
2690 cell phone headset
2593 used cellular phone
2586 cellular phone case
2524 cellular phone lookup
2524 t mobile cellular phone
2266 sprint pcs cellular phone
2202 pre paid cellular phone
2180 cellular phone provider
2162 wholesale cellular phone
2151 refurbished cellular phone
2118 history of cellular phone
2079 cellular phone cover
2003 cellular phone rate
1921 cellular phone ring tone
1898 cingular cellular phone
1658 reverse cellular phone look up
1633 panasonic cellular phone
1570 cellular phone game
1546 reverse cellular phone numbers
1541 cellular phone comparison
1534 cellular phone service provider
1505 audiovox cellular phone
1503 reverse cellular phone lookup
1489 best cellular phone
1489 international cellular phone rental
1485 cellular one phone
1435 blue tooth cellular phone
1418 free cellular phone downloads
1418 cellular phone number reverse lookup
1389 free cellular phone ringer
1378 cellular phone number search
1344 att cellular phone
1321 cellular phone number look up
1316 new cellular phone
1287 cellular phone picture
1274 free cellular phone game
1266 cellular phone number lookup
1264 cellular phone downloads
1251 unlock cellular phone
1221 camera cellular phone
1188 sony cellular phone
1179 pda cellular phone
1169 cellular phone antenna
1131 cellular phone ring
1121 unlocked cellular phone
1095 wholesale cellular phone accessory
1095 cellular phone for sale
1089 cellular phone number directory
1073 free cellular phone ring tone
1066 free prepaid cellular phone
1063 no credit check cellular phone
1056 cellular phone repair
1046 siemens cellular phone
1039 cellular phone ringer
1037 compare cellular phone
1000 alltel cellular phone
995 cellular phone rating
972 cellular phone screensaver
968 cellular phone store
915 wireless cellular phone
906 compare cellular phone plan
903 verizon wireless cellular phone
879 buy cellular phone
810 find cellular phone number
803 kyocera cellular phone
778 sanyo cellular phone
769 discount cellular phone
762 cellular phone new york
736 pay as you go cellular phone
732 mobile cellular phone
729 free cellular phone screensaver
700 cellular phone book
Can somebody fill me in on why this would be, unless of course nobody made any search with the plural "phones," which I consider pretty unlikely. Is there something I'm missing about how the tool is supposed to work?