Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
van nhanh » van thanh, van hanh, van khanh
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
thai cau » thai cao, toan cau, thai van
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
tu sach » thu sach, su sach, te sach
y nang » ky nang, ly nang, v nang
co hoi » co hoc, co loi
o hai » co hai, so hai, o lai
o hoi » o hoc, o hoa

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 y nang ((((o hoi) or (co hoi))) or (o hai)). hieu van cam duc van nhanh thai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((((o hoi) OR (co hoi))) OR (o hai)). hieu van cam duc van nhanh thai cau tren.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((((o hoi) or (co hoi))) or (o hai)). hieu van cam duc van nhanh thai cau tren*.