Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hang van » hoang van, dang van, tang van
coc luoc » coc luc, hoc nuoc, hoc duoc
luoc gia » quoc gia, luc gia, luong gia
thanh di » thanh doi, thanh de, thanh do
cau tren » cu tren, ca tren, cau treo
dau tren » dau tien, dat tren, dau tieng
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
ve coc » ve cuoc, ve cac, ve co

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((hang van) or (hang va)) hoi. hieu ve coc luoc gia thanh di ((cau tren) OR (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((hang van) OR (hang va)) hoi. hieu ve coc luoc gia thanh di ((cau tren) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((hang van) or (hang va)) hoi. hieu ve coc luoc gia thanh di ((cau tren) OR (dau tren))".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((hang van) or (hang va)) hoi. hieu ve coc luoc gia thanh di ((cau tren) OR (dau tren))*.