Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thu nang » thu hang, thu bang, tho nang
phat tai » pham tai, phap tai, chat tai
thi nang » thi cong, ki nang, thi hanh
chat cuu » chat huu, chat cua, cham cuu
va chat » van chat, cao chat, hoa chat
tai cua » thai cua, tai cuc, tri cua
hieu va » lieu va, hieu qua
cuu va » cuu van, cuu ve
cua cu » cua chu, cua cau, cua su
x hoi » xa hoi, o hoi, x ho

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) OR (toc sach)) ((thu nang) or (thi nang)) x hoi. hieu va chat cuu va phat tai cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ((thu nang) OR (thi nang)) x hoi. hieu va chat cuu va phat tai cua cu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ((thu nang) or (thi nang)) x hoi. hieu va chat cuu va phat tai cua cu".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ((thu nang) or (thi nang)) x hoi. hieu va chat cuu va phat tai cua cu*.