Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
luoc van » luoc can, luoc va, luot van
su triet » su viet, su tien, ve triet
te sach » toc sach
nang xa » nang x, lang xa, nang ma
hieu su » hieu sau, tieu su, hieu so
su nhan » cu nhan, tu nhan, su nha
luc van » luu van, duc van, luc va
hanh va » hang va, hanh vi
y nang » ky nang, ly nang, v nang

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) or (te sach)) y nang xa hoi. hieu su nhan ((luc van) OR (luoc van)) hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (te sach)) y nang xa hoi. hieu su nhan ((luc van) OR (luoc van)) hanh va su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (te sach)) y nang xa hoi. hieu su nhan ((luc van) OR (luoc van)) hanh va su triet".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (te sach)) y nang xa hoi. hieu su nhan ((luc van) OR (luoc van)) hanh va su triet*.