Perhaps you should try some spelling variations:
giang day » gian dan
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
sach ty » sach y, sach tu, sach thu
nam luc » nhan luc, nam thuc, nam duoc
va danh » va dinh, va dan, va hanh
danh va » doanh va, hanh va, anh va
te sach » toc sach
va cau » van cau, va cac, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty ((giang day) or (hang va)) hoe. hieu van ((nam luc) OR (nang luc)) va danh va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((giang day) OR (hang va)) hoe. hieu van ((nam luc) OR (nang luc)) va danh va cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty ((giang day) or (hang va)) hoe. hieu van ((nam luc) OR (nang luc)) va danh va cau tren".
• Adding a wildcard symbol may retrieve word variants: te sach ty ((giang day) or (hang va)) hoe. hieu van ((nam luc) OR (nang luc)) va danh va cau tren*.