Perhaps you should try some spelling variations:
thieu nien » thien nhien
nhan dang » nhan dan, phan dang, tran dang
luc nhan » luc nhat, cu nhan, tue nhan
nien cac » vien cac, dien cac, bien cac
cau tren » cu tren, dau tren, ca tren
ty hang » ly hang, thi hang, thu hang
cac luc » cau luc, coc luc, cac nuoc
ty nang » ky nang, ly nang, ty nong
dang va » dang van, dang vat, hang va
tu sach » thu sach, su sach, te sach
ma hoi » mai hoi, xa hoi, ma hoa
va cau » van cau, va cac, va dau

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 ((ty nang) or (((ty hang) OR (ty xang)))) ma hoi. thieu nien cac luc nhan dang va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (((ty hang) OR (ty xang)))) ma hoi. thieu nien cac luc nhan dang va cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) or (((ty hang) OR (ty xang)))) ma hoi. thieu nien cac luc nhan dang va cau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) or (((ty hang) OR (ty xang)))) ma hoi. thieu nien cac luc nhan dang va cau tren*.