Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
thuoc sac » thuoc sach, thuoc dac, thuoc sai
thai cau » thai cao, toan cau, thai van
cau tren » cu tren, dau tren, ca tren
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
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: thuoc sac ky nang ((o hoi) or (o hai)). hieu ve cac ((xuc van) or (duc van)) nhanh thai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sac ky nang ((o hoi) OR (o hai)). hieu ve cac ((xuc van) OR (duc van)) nhanh thai cau tren.
• Adding a wildcard symbol may retrieve word variants: thuoc sac ky nang ((o hoi) or (o hai)). hieu ve cac ((xuc van) or (duc van)) nhanh thai cau tren*.