Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
van nhanh » van thanh, van hanh, van khanh
dau tren » dau tien, dat tren, dau tieng
thai dau » thau dau, thai dac, thi dau
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
hieu van » hieu va, thien van, lieu va
cac xuc » cam xuc, chat xuc, cac cuoc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
o lai » o lao
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 ky nang ((o hoi) or (o lai)). hieu van ((cac xuc) OR (cac nuoc)) van nhanh thai dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((o hoi) OR (o lai)). hieu van ((cac xuc) OR (cac nuoc)) van nhanh thai dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((o hoi) or (o lai)). hieu van ((cac xuc) OR (cac nuoc)) van nhanh thai dau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((o hoi) or (o lai)). hieu van ((cac xuc) OR (cac nuoc)) van nhanh thai dau tren*.