Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
gat thanh » dat thanh, tat thanh, vat thanh
khoa hoi » khoan hoi, khoa hoc, khoa doi
su triet » su tien, ve triet
su viet » so viet
ky hang » ky nang, ly hang, ky dang
hoa hoi » hoa hoc, hoa doi, hoc hoi
hieu ve » hieu va, hieu van
thu gat » thu gan, thu nhat, thu ngan
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
ve nam » he nam, va nam, le nam

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky hang ((hoa hoi) OR (khoa hoi)). hieu ve nam thu gat thanh tai ((su triet) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky hang ((hoa hoi) OR (khoa hoi)). hieu ve nam thu gat thanh tai ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky hang ((hoa hoi) OR (khoa hoi)). hieu ve nam thu gat thanh tai ((su triet) or (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky hang ((hoa hoi) OR (khoa hoi)). hieu ve nam thu gat thanh tai ((su triet) or (su viet))*.