Perhaps you should try some spelling variations:
khanh thai » nhanh thai, khanh thanh, khanh thuan
van khanh » van thanh, van hanh, van anh
thu sach » tu sach, thuat sach, thuoc sach
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
cac xuc » cam xuc, cac nuoc, chat xuc
xuc van » duc van, luc van, vuc van
thai cu » thai cua, thai xu, thi cu
cu tren » tu tren, dua tren
ve cac » va cac, vien cac
o hoc » co hoc, mo hoc, so hoc
o hai » co hai, so hai, o lai
o hoi » co hoi, 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: thu sach ky nang ((((o hoi) OR (o hoc))) or (o hai)). hieu ve cac xuc van khanh thai cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((((o hoi) OR (o hoc))) OR (o hai)). hieu ve cac xuc van khanh thai cu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ((((o hoi) OR (o hoc))) or (o hai)). hieu ve cac xuc van khanh thai cu tren".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((((o hoi) OR (o hoc))) or (o hai)). hieu ve cac xuc van khanh thai cu tren*.