Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cua nuoc » cua quoc, cua nguoi, cua thuoc
lang xa » lang ha, dang xay, lang van
ve cham » va cham, ve chat, vu cham
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cua duc » cua tuc, cua quoc
ve cam » ve cac, va cam, ve cai
sach o » sach lo, sac o, sach y
o lang » hoa lang, hoi lang

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 o lang xa hoi. hieu ((ve cam) or (ve cham)) thuc va hanh vi ((cua duc) or (cua nuoc))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach o lang xa hoi. hieu ((ve cam) OR (ve cham)) thuc va hanh vi ((cua duc) OR (cua nuoc)).
• Adding a wildcard symbol may retrieve word variants: toc sach o lang xa hoi. hieu ((ve cam) or (ve cham)) thuc va hanh vi ((cua duc) or (cua nuoc))*.