Perhaps you should try some spelling variations:
thanh tan » thanh toan, thanh tuan, thanh san
doc sach » hoc sach, toc sach, nuoc sach
tuc thai » thuc thai, toc thai, tuc hai
hieu van » hieu va, thien van, hieu ve
thuc tai » thuc thai, thuoc tai, thuc tap
tan cua » than cua, tang cua, toan cua
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky lang xa hoi. ((hieu van) OR (lieu va)) nam ((tuc thai) or (thuc tai)) thanh tan cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky lang xa hoi. ((hieu van) OR (lieu va)) nam ((tuc thai) OR (thuc tai)) thanh tan cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ky lang xa hoi. ((hieu van) OR (lieu va)) nam ((tuc thai) or (thuc tai)) thanh tan cua te".
• Adding a wildcard symbol may retrieve word variants: doc sach ky lang xa hoi. ((hieu van) OR (lieu va)) nam ((tuc thai) or (thuc tai)) thanh tan cua te*.