Perhaps you should try some spelling variations:
duc tren » duoc tren, dua tren, duc tien
hieu van » hieu va, thien van, lieu va
van nhan » van phan, van thanh, danh nhan
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
te sach » toc sach
nang di » nang du, hang di, nang ji
tu sach » thu sach, su sach, tu cach
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
di duc » do duc, di du, oi duc

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