Perhaps you should try some spelling variations:
dung tren » dung trong, dung trung
thanh lap » thanh san, phan lap, thanh hai
cham luc » cham soc, nhan luc, cham cuu
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
tao hoi » tao khoi, tao boi, tay hoi
ky sang » ky dang, ky tang, duy sang
luc va » duc va, tuc va, loc va
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky sang) OR (ky nang)) tao hoi. hieu ve cham luc va thanh lap ((dung tren) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky sang) OR (ky nang)) tao hoi. hieu ve cham luc va thanh lap ((dung tren) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky sang) OR (ky nang)) tao hoi. hieu ve cham luc va thanh lap ((dung tren) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky sang) OR (ky nang)) tao hoi. hieu ve cham luc va thanh lap ((dung tren) or (cua tu))*.