Perhaps you should try some spelling variations:
diem thuan » diem thuc, hien thuan, dinh thuan
thuat lanh » thuat lap, thuat san
kxy thuat » ki thuat, my thuat, ky thua
thu sach » tu sach, thuat sach, thuoc sach
lanh kxy » hanh ky, lanh lay
thuat o » thuat do
do khi » doi khi, do thi, co khi
o khi » co khi, bo khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( thu sach ((ky thuat) or (diem thuan)) do khi ) or ( thuat lanh kxy thuat o khi ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thu sach ((ky thuat) OR (diem thuan)) do khi ) OR ( thuat lanh kxy thuat o khi )).
• Adding a wildcard symbol may retrieve word variants: (( thu sach ((ky thuat) or (diem thuan)) do khi ) or ( thuat lanh kxy thuat o khi ))*.