Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
thac toc » cac toc, thac cac, thi toc
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
hac tuc » thai tuc
vai cua » dai cua, hai cua, lai cua
ky tang » ky nang, kho tang, ky trong
ky dang » ky nang, ky danh
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: su sach ((ky dang) or (ky tang)) xa hoi. hieu van ((hac tuc) OR (thac toc)) gia thanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky dang) OR (ky tang)) xa hoi. hieu van ((hac tuc) OR (thac toc)) gia thanh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky dang) or (ky tang)) xa hoi. hieu van ((hac tuc) OR (thac toc)) gia thanh vai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky dang) or (ky tang)) xa hoi. hieu van ((hac tuc) OR (thac toc)) gia thanh vai cua te*.