^ Many if not all of the "missing" routes are county rather than state routes. Travel Mapping doesn't include county routes anywhere in the U.S., except for some county-maintained freeways (none of those in Hawaii).
It doesn't help that Hawaii's counties use the same kind of route markers as Hawaii DOT, with only "end state maintenance" signs marking where the state network ends. Hawaii used to have both state and county routes in a single highway system, but in 1968 Hawaii DOT split that system into separate state and county networks. We cover only the state routes defined by Hawaii DOT.
On specific routes you mention, the HI 340 part of the Kahekili Highway, west to the "end state maintenance" sign, is in TM. The rest of it is county 340. HI 3400 is in TM, but not what is signed as route 33 or 330 in Wailuku. "HI-3200" into Iao Valley is county 320. HI 31 from Kihei to Wailua is in TM; the rest of route 31 (including part between Hana and Kipahulu sometimes mis-signed as route 360) is a county route. 390, 365, and 371 are all county routes which were never part of the state highway system.
Kauai, Molokai, and Hawaii (Big Island) have signed county routes not included in TM. Honolulu County doesn't have any numbered county highways, though there are some signs remaining from a few former county routes.