One problem with the /oo/ and /ue/ sounds, apart from having slightly different pronunciations in different accents, is that after /l/ they can sound quite similar: flu/flew, fluke.
The main spellings for the /ue/ sound are 'u-e' (or open u) and 'ue':
e.g. use, unit, cute, duty, reduce, salute ....cue, due, argue, avenue....
In the stem of words the spelling is fairly dominant, in at least 137 words, with just 26 exceptions:
eucalyptus, ewer, feud, feudal, jewel, lewd, neutral, newt,
nuclear, beauty, nuisance, pewter, pneumatic, pseudo, rheumatism,
sewage, steward, suicide, suitable, suitcase, juice, Tuesday,
you/ewe/yew, youth.
In endings the spellings are less predictable. (I can list those too, if it would help, but u would have to ask for them, otherwise some people might call it 'spam' and try to get me banned for posting a list.)
One thing which helps to muddy the /oo/ and /u-e/ issue is that 'u-e' is often also used to spell long /oo/ (rude, crude, brute, crucial...).