Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
hang tai » hang va, dung tai
hieu van » hieu va, thien van, lieu va
trung va » truong va, trang va, trung ha
tu sach » su sach, te sach, tu cach
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
luc va » duc va, tuc va, loc va
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: ((tu sach) OR (thu sach)) y nang xa hoi. hieu van nam ((luc va) or (trung va)) hang tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y nang xa hoi. hieu van nam ((luc va) OR (trung va)) hang tai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) y nang xa hoi. hieu van nam ((luc va) or (trung va)) hang tai cua tre*".