Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
hieu vien » hieu hien, hieu viec, thieu nien
vien bac » vien bach, vien cac, mien bac
te sach » toc sach
thuc va » thuc vat, thuc dan, thuc day
chi tro » chieu tro, chi thoi
cho tre » cho thue, khoe tre
sach ty » sach y, sach tu, sach thu
thue va » thuyet va, thuc vat, thuat va
dang xa » dang xay, lang xa, dang ha
ty dang » ty xang, ky dang, ty hang

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty dang xa hoi. hieu vien bac ((thue va) OR (thuc va)) thanh toan ((chi tro) or (cho tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty dang xa hoi. hieu vien bac ((thue va) OR (thuc va)) thanh toan ((chi tro) OR (cho tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty dang xa hoi. hieu vien bac ((thue va) OR (thuc va)) thanh toan ((chi tro) or (cho tre))".
• Adding a wildcard symbol may retrieve word variants: te sach ty dang xa hoi. hieu vien bac ((thue va) OR (thuc va)) thanh toan ((chi tro) or (cho tre))*.