I speak a little Thai so I think I know what you are referring to. It's not a matter of lung air but a matter of how you let the air out when you are speaking, and when.
The phonotax, which sound structure syllables and words have, is very different for English and Thai.
1. the number of possible consonants phonemes in the beginning of a Thai syllable is considerably larger than at the end of the syllable
2. the number of consonant clusters in the beginning of the syllable is limited in Thai,and there are no syllable final clusters.
1- Consonant phonemes in syllable initial and syllable final position
The Thai syllable and word can in principle only end in a vowel, a nasal stop, a glide or an unreleased stop.
Where English initially in has a distinction between voiced vs voiceless stop, eg /d/ vs /t/, Thai has a threeway distinction voiced vs voiceless vs aspirated stop - /d/ vs /t/ vs /th/ :
At the end of syllable English has in general then same voiced vs voiceless distinction for stops, but in Thai there no voiced vs voiceless vs aspirated stop, only the inaudible/unreleased /t̚/. You could say that the phonemes /d, t, th, / have the same allophone [t̚] in final position, or that the distinction is neutralised to [t̚]
Furthermore this 'neutralisation' also includes all the obstruents in Thai
- /d, t, th, / and /s,tɕ, tɕh/ are all neutralized to [t̚] in a syllable final
/b, p, ph, f/ are all neutralized to final [p']
/g, k, kh/ are all neutralized to final [k']
Also for sonorants
- /n, r, l/ are neutralized to final [n]
This difference has a major impact on the release of stops inside the phrase
To give a brief example
- In English 'rat king' the /t/ would be released before the onset of /k/
- In Thai 'rat̚king' the /t̚ k/ sequence involves no release whatsoever.
2 Consonant clusters
Initial cluster in Thai are limited to to stop+/r, l, w/ initially:
- pr-, phr-, pl, phl-
- kr-, khr-, kl-, khl-, kw-, khw-
, and there are no final clusters at all.
This means that eg the initial clusters like English
- sp- st- sk- spr-, skr- spl-
do not occur, and final clusters as in words like
- 'lift', 'lips', and 'lisp' 'list'
are simply not possible in Thai.