Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
luc nhan » luc nhat, cu nhan, tue nhan
hang ve » hang va, hanh ve, hang ke
luc nha » luc nhat, luc ha, luc nua
te sach » toc sach
ty nang » ty xang, ty hang, ly nang
hieu va » lieu va, hieu qua
va cau » van cau, va cac, va dau
ve cau » ke cau, ve cac, le cau
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ty nang) or (ky nang)) x hoi. hieu va cau ((luc nha) OR (luc nhan)) hang ve cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ky nang)) x hoi. hieu va cau ((luc nha) OR (luc nhan)) hang ve cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty nang) or (ky nang)) x hoi. hieu va cau ((luc nha) OR (luc nhan)) hang ve cau tren".
• Adding a wildcard symbol may retrieve word variants: te sach ((ty nang) or (ky nang)) x hoi. hieu va cau ((luc nha) OR (luc nhan)) hang ve cau tren*.