There are thousands! Here are a sampler:
Kabalas
Kayaker
Karmic
Kaput
Kanji
Try ki and ka.
Some Scrabble words that start with U are:upususeunderuncleurineuntoundounclearunnecessaryumbrellaurgentuglyusefulumberutilityunusualunguentuniversalupperundulyundecidedutmostunitunmanageable
Words starting with USHUsherUsheranceUsherancesUsherdomUsherdomsUsheredUsheressesUsheretteUsherettesUsheringUsheringsUsherlessUsherredUsherringUshersUshershipUsherships
knowledge
Axe.
avenue??
effecteffigyefforteffuse
The two letter words that begins with K are ky, kb and kl. These three two letter words are recognized in the Scrabble Dictionary. In addition ka is also known as the river in Nigeria.
There are no words that start with ZH, here are some words that start with z:ZacatonZaddickZaffarsZaffersZaffirsZaffresZaggingZaikaisZamarraZamarroZananasZandersZaniestZanyishZapateoZappersZappierZappingZaptiahZaptiehZarebasZareebaZaribasZealotsZealousZeatinsZebecksZebraicZebranoZebrassZebrineZebroidZecchinZechinsZedoaryZelkovaZemstvaZemstvoZenaidaZenanasZenithsZeoliteZephyrsZeppoleZeppoliZeroingZestersZestfulZestierZestilyZestingZeugmasZibethsZiggingZigzagsZikuratZilchesZillahsZillionZincateZincifyZincingZinciteZinckedZincoidZincousZinganiZinganoZingaraZingareZingariZingaroZingersZingierZingingZinkifyZinniasZiplessZiplockZippersZippierZippingZirconsZithernZithersZizzledZizzlesZlotiesZlotychZoarialZoariumZocalosZodiacsZoeciumZoisiteZombiesZombifyZonallyZonatedZonkingZonulaeZonularZonulasZonulesZooeciaZoogenyZoogleaZooidalZooiestZoologyZoomingZooningZootierZootomyZorillaZorilleZorilloZostersZouavesZoysiasZydecosZygomasZygosesZygosisZygotesZygoticZymasesZymogenZymosanZymosesZymosisZymoticZymurgyZyzzyva
ivy and ivory
tablet table
Zigzag ? i think