Perhaps you should try some spelling variations:
tru nang » tra nang, tri nang, truc nano
thac toc » cac toc, thac cac, thi toc
hanh hai » thanh hai, nhanh hai, hang hai
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
tu nang » tu nong, tu nano, tu lang
hieu va » lieu va, hieu qua
va thac » van thac, va thuc, va tac
va hanh » van hanh, va thanh, va danh
toc va » hoc va, toc ta, tuc va
hai su » hai vu, lai su, hai so

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 ((tu nang) OR (tru nang)) xa hoi. hieu va thac toc va hanh hai su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((tu nang) OR (tru nang)) xa hoi. hieu va thac toc va hanh hai su triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((tu nang) OR (tru nang)) xa hoi. hieu va thac toc va hanh hai su triet*.