Perhaps you should try some spelling variations:
chay tren » thai tren, ca tren, chay dien
canh hanh » xanh hanh, canh tranh, danh thanh
cau tren » cu tren, dau tren, ca tren
hanh va » hang va, hanh vi
cau luc » cau truc, cau phuc
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
ty nang » ky nang, ty hang, ly nang
va cau » van cau, va cac, va dau
o hoi » co hoi, o hoc, o hai

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