Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
chat soc » cham soc, chat hoc, chat song
chat doc » chat hoc, chau doc, thuat doc
cua viet » ca viet, cua vat, cua dieu
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
va lanh » va lang, va danh, va hanh
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: vu sach ky nang x hoi. hieu van ((chat soc) OR (chat doc)) va lanh dao ((cua viet) or (hoa viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang x hoi. hieu van ((chat soc) OR (chat doc)) va lanh dao ((cua viet) OR (hoa viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang x hoi. hieu van ((chat soc) OR (chat doc)) va lanh dao ((cua viet) or (hoa viet))".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang x hoi. hieu van ((chat soc) OR (chat doc)) va lanh dao ((cua viet) or (hoa viet))*.