Hi, I'm new to these boards and I can't seem to figure something out.

In some routings there are parentheses, such as is in:
BKK-TYO/NGO-HNL(UA/HA)ITO/OGG/LIH/KOA(UA/HA/HA)HNL-SEA-SFO-LAX
-SJC/SNA/BUR/CLD/ONT/SAN-SMF/SAC-SFO

I understand the whole "/" and "-" thing, but what does "(UA/HA)" mean?

More specifically, I'm trying to book SFO-BKK using OZ KLE6M, but I can't seem to get a legal routing using ITA. The routing options are:

BKK(UL)HKG-SEL-LAX(UA)SFO
BKK(UL)HKG-SEL-SFO/SEA-LAX(UA)SFO
BKK(UL)HKG-SEL-LAX(AA)SFO
BKK(UL)HKG-SEL-SFO/SEA-LAX(AA)SFO
BKK(UL)HKG-SEL-LAX(AS)SFO
BKK(UL)HKG-SEL-SFO/SEA-LAX(AS)SFO
BKK(UL)HKG-SEL-SEA(OZ/UA)SFO
BKK(UL)HKG-SEL-LAX/SFO-SEA(OZ/UA/UA)SFO
BKK(UL)HKG-SEL-SEA(AS)SFO
BKK(UL)HKG-SEL-LAX/SFO-SEA(AS)SFO
BKK(UL)HKG-SEL-SFO
BKK(UL)HKG-SEL-LAX/SEA-SFO
BKK(CX)HKG-SEL-LAX(UA)SFO
BKK(CX)HKG-SEL-SFO/SEA-LAX(UA)SFO
BKK(CX)HKG-SEL-LAX(AA)SFO
BKK(CX)HKG-SEL-SFO/SEA-LAX(AA)SFO
BKK(CX)HKG-SEL-LAX(AS)SFO
BKK(CX)HKG-SEL-SFO/SEA-LAX(AS)SFO
BKK(CX)HKG-SEL-SEA(OZ/UA)SFO
BKK(CX)HKG-SEL-LAX/SFO-SEA(OZ/UA/UA)SFO
BKK(CX)HKG-SEL-SEA(AS)SFO
BKK(CX)HKG-SEL-LAX/SFO-SEA(AS)SFO
BKK(CX)HKG-SEL-SFO
BKK(CX)HKG-SEL-LAX/SEA-SFO
BKK(TG)HKG-SEL-LAX(UA)SFO
BKK(TG)HKG-SEL-SFO/SEA-LAX(UA)SFO
BKK(TG)HKG-SEL-LAX(AA)SFO
BKK(TG)HKG-SEL-SFO/SEA-LAX(AA)SFO
BKK(TG)HKG-SEL-LAX(AS)SFO
BKK(TG)HKG-SEL-SFO/SEA-LAX(AS)SFO
BKK(TG)HKG-SEL-SEA(OZ/UA)SFO
BKK(TG)HKG-SEL-LAX/SFO-SEA(OZ/UA/UA)SFO
BKK(TG)HKG-SEL-SEA(AS)SFO
BKK(TG)HKG-SEL-LAX/SFO-SEA(AS)SFO
BKK(TG)HKG-SEL-SFO
BKK(TG)HKG-SEL-LAX/SEA-SFO
BKK(CI)HKG-SEL-LAX(UA)SFO
BKK(CI)HKG-SEL-SFO/SEA-LAX(UA)SFO
BKK(CI)HKG-SEL-LAX(AA)SFO
BKK(CI)HKG-SEL-SFO/SEA-LAX(AA)SFO
BKK(CI)HKG-SEL-LAX(AS)SFO
BKK(CI)HKG-SEL-SFO/SEA-LAX(AS)SFO

BKK(CI)HKG-SEL-SEA(OZ/UA)SFO
BKK(CI)HKG-SEL-LAX/SFO-SEA(OZ/UA/UA)SFO
BKK(CI)HKG-SEL-SEA(AS)SFO
BKK(CI)HKG-SEL-LAX/SFO-SEA(AS)SFO
BKK(CI)HKG-SEL-SFO
BKK(CI)HKG-SEL-LAX/SEA-SFO
BKK-SEL-LAX(UA)SFO
BKK-SEL-SFO/SEA-LAX(UA)SFO
BKK-SEL-LAX(AA)SFO
BKK-SEL-SFO/SEA-LAX(AA)SFO
BKK-SEL-LAX(AS)SFO
BKK-SEL-SFO/SEA-LAX(AS)SFO
BKK-SEL-SEA(OZ/UA)SFO
BKK-SEL-LAX/SFO-SEA(OZ/UA/UA)SFO
BKK-SEL-SEA(AS)SFO
BKK-SEL-LAX/SFO-SEA(AS)SFO
BKK-SEL-SFO

I think if I can figure out the parenthesis thing, I might get a valid routing...

Thanks!