Perhaps you should try some spelling variations:
phan thanh » pham thanh, ban thanh, van thanh
luan phan » luan van, luan hoan
thanh cau » thanh chau, thanh mau, nhanh cau
xuc luan » luc luan, xu luan, nuoc luan
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cac xuc » cam xuc, cac nuoc, chat xuc
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
o hoc » co hoc, mo hoc, so hoc
o hai » co hai, so hai, o lai

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 hoc) or (o hai)). hieu ve cac xuc luan phan thanh cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((o hoc) OR (o hai)). hieu ve cac xuc luan phan thanh cau tren*.