Perhaps you should try some spelling variations:
thang cau » hang cau, thong cau, thanh chau
van khanh » van thanh, van hanh, van anh
van nhanh » van thanh, van hanh, van nhan
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, te sach
cac xuc » cam xuc, cac nuoc, chat xuc
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
o hai » co hai, so hai, o lai
o hoi » co 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 ky nang ((o hoi) or (o hai)). hieu va cac xuc ((van nhanh) OR (van khanh)) thang cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((o hoi) OR (o hai)). hieu va cac xuc ((van nhanh) OR (van khanh)) thang cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((o hoi) or (o hai)). hieu va cac xuc ((van nhanh) OR (van khanh)) thang cau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((o hoi) or (o hai)). hieu va cac xuc ((van nhanh) OR (van khanh)) thang cau tren*.