Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thu nang » thi nang, thu hang, thu bang
phat tai » pham tai, phap tai, chat tai
thi cong » tai cong, thien cong
chat cua » nhat cua, chat va, chat huu
cham cuu » cap cuu
tai cua » thai cua, tai cuc, tri cua
hieu va » lieu va, hieu qua
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: toc sach ((thu nang) or (thi cong)) x hoi. hieu va ((cham cuu) or (chat cua)) va phat tai cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((thu nang) OR (thi cong)) x hoi. hieu va ((cham cuu) OR (chat cua)) va phat tai cua cu.
• Adding a wildcard symbol may retrieve word variants: toc sach ((thu nang) or (thi cong)) x hoi. hieu va ((cham cuu) or (chat cua)) va phat tai cua cu*.