Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
cham tuc » nham thuc, pham thuc, tham thuc
nang xa » nang x, lang xa, nang ma
dan mat » dang mat, dan dat, dan lat
mat cua » ma cua, manh cua, mang cua
tuc va » thuc va, truc va, tuc xa
va dan » ca dan, va dao, va dau
cua te » cua tu

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) or (hoc sinh)) ky nang xa hoi. hieu van cham tuc va dan mat cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sinh)) ky nang xa hoi. hieu van cham tuc va dan mat cua te.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sinh)) ky nang xa hoi. hieu van cham tuc va dan mat cua te*.