Perhaps you should try some spelling variations:
tren luyen » trinh luyen, tien quyen, tre tuyen
kin tren » dinh tren, gian tren, sinh tren
luyen ky » truyen ky, luyen de
sang ma » tang ma, sang tao, mang may
ky sang » ky dang, ky tang, duy sang
nang ma » tang ma, nang cao, mang may
bao bi » bao ai, sao bi
tuoi 7 » tuoi 1
bi kin » bi kip, bai kinh
bo bi » bo bai, bot bi, so bi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( (bot OR both) bi kin tren luyen ky nang ma. Đo tuoi 7-15 ) or ( ((bo bi) or (bao bi)) kip ren luyen ky sang ma. Đo tuoi 7-15 ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( (bot OR both) bi kin tren luyen ky nang ma. Đo tuoi 7-15 ) OR ( ((bo bi) OR (bao bi)) kip ren luyen ky sang ma. Đo tuoi 7-15 )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( (bot OR both) bi kin tren luyen ky nang ma. Đo tuoi 7-15 ) or ( ((bo bi) or (bao bi)) kip ren luyen ky sang ma. Đo tuoi 7-15 ))".
• Adding a wildcard symbol may retrieve word variants: (( (bot OR both) bi kin tren luyen ky nang ma. Đo tuoi 7-15 ) or ( ((bo bi) or (bao bi)) kip ren luyen ky sang ma. Đo tuoi 7-15 ))*.